diff --git a/java/com/google/gerrit/server/AssigneeStatusUpdate.java b/java/com/google/gerrit/server/AssigneeStatusUpdate.java
deleted file mode 100644
index 812aad1..0000000
--- a/java/com/google/gerrit/server/AssigneeStatusUpdate.java
+++ /dev/null
@@ -1,35 +0,0 @@
-// Copyright (C) 2019 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.google.gerrit.server;
-
-import com.google.auto.value.AutoValue;
-import com.google.gerrit.entities.Account;
-import java.time.Instant;
-import java.util.Optional;
-
-/** Change to an assignee's status. */
-@AutoValue
-public abstract class AssigneeStatusUpdate {
-  public static AssigneeStatusUpdate create(
-      Instant ts, Account.Id updatedBy, Optional<Account.Id> currentAssignee) {
-    return new AutoValue_AssigneeStatusUpdate(ts, updatedBy, currentAssignee);
-  }
-
-  public abstract Instant date();
-
-  public abstract Account.Id updatedBy();
-
-  public abstract Optional<Account.Id> currentAssignee();
-}
diff --git a/java/com/google/gerrit/server/notedb/ChangeNoteFooters.java b/java/com/google/gerrit/server/notedb/ChangeNoteFooters.java
index 771d72b..3be55ea 100644
--- a/java/com/google/gerrit/server/notedb/ChangeNoteFooters.java
+++ b/java/com/google/gerrit/server/notedb/ChangeNoteFooters.java
@@ -19,7 +19,6 @@
 /** Footers, that can be set in NoteDb commits. */
 public class ChangeNoteFooters {
   public static final FooterKey FOOTER_ATTENTION = new FooterKey("Attention");
-  public static final FooterKey FOOTER_ASSIGNEE = new FooterKey("Assignee");
   public static final FooterKey FOOTER_BRANCH = new FooterKey("Branch");
   public static final FooterKey FOOTER_CHANGE_ID = new FooterKey("Change-id");
   public static final FooterKey FOOTER_COMMIT = new FooterKey("Commit");
diff --git a/java/com/google/gerrit/server/notedb/ChangeNotes.java b/java/com/google/gerrit/server/notedb/ChangeNotes.java
index 52f540d..c75fd29 100644
--- a/java/com/google/gerrit/server/notedb/ChangeNotes.java
+++ b/java/com/google/gerrit/server/notedb/ChangeNotes.java
@@ -16,7 +16,6 @@
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkState;
-import static com.google.common.collect.ImmutableSet.toImmutableSet;
 import static com.google.gerrit.entities.RefNames.changeMetaRef;
 import static java.util.Comparator.comparing;
 
@@ -29,7 +28,6 @@
 import com.google.common.collect.ImmutableSortedMap;
 import com.google.common.collect.ImmutableSortedSet;
 import com.google.common.collect.ListMultimap;
-import com.google.common.collect.Lists;
 import com.google.common.collect.Multimaps;
 import com.google.common.collect.Ordering;
 import com.google.common.collect.Sets;
@@ -53,7 +51,6 @@
 import com.google.gerrit.entities.RobotComment;
 import com.google.gerrit.entities.SubmitRecord;
 import com.google.gerrit.entities.SubmitRequirementResult;
-import com.google.gerrit.server.AssigneeStatusUpdate;
 import com.google.gerrit.server.ReviewerByEmailSet;
 import com.google.gerrit.server.ReviewerSet;
 import com.google.gerrit.server.ReviewerStatusUpdate;
@@ -498,26 +495,6 @@
     return state.submitRequirementsResult();
   }
 
-  /**
-   * Returns an ImmutableSet of Account.Ids of all users that have been assigned to this change. The
-   * order of the set is the order in which they were assigned.
-   */
-  public ImmutableSet<Account.Id> getPastAssignees() {
-    return Lists.reverse(state.assigneeUpdates()).stream()
-        .map(AssigneeStatusUpdate::currentAssignee)
-        .filter(Optional::isPresent)
-        .map(Optional::get)
-        .collect(toImmutableSet());
-  }
-
-  /**
-   * Returns an ImmutableList of AssigneeStatusUpdate of all the updates to the assignee field to
-   * this change. The order of the list is from most recent updates to least recent.
-   */
-  public ImmutableList<AssigneeStatusUpdate> getAssigneeUpdates() {
-    return state.assigneeUpdates();
-  }
-
   /** Returns an ImmutableSet of all hashtags for this change sorted in alphabetical order. */
   public ImmutableSet<String> getHashtags() {
     return ImmutableSortedSet.copyOf(state.hashtags());
diff --git a/java/com/google/gerrit/server/notedb/ChangeNotesCache.java b/java/com/google/gerrit/server/notedb/ChangeNotesCache.java
index 0f2c877..2d3902c 100644
--- a/java/com/google/gerrit/server/notedb/ChangeNotesCache.java
+++ b/java/com/google/gerrit/server/notedb/ChangeNotesCache.java
@@ -181,8 +181,6 @@
           + P
           + list(state.reviewerUpdates(), 4 * O + K + K + P)
           + P
-          + list(state.assigneeUpdates(), 4 * O + K + K)
-          + P
           + set(state.attentionSet(), 4 * O + K + I + str(15))
           + P
           + list(state.allAttentionSetUpdates(), 4 * O + K + I + str(15))
diff --git a/java/com/google/gerrit/server/notedb/ChangeNotesParser.java b/java/com/google/gerrit/server/notedb/ChangeNotesParser.java
index 467095c..0ee0689 100644
--- a/java/com/google/gerrit/server/notedb/ChangeNotesParser.java
+++ b/java/com/google/gerrit/server/notedb/ChangeNotesParser.java
@@ -15,7 +15,6 @@
 package com.google.gerrit.server.notedb;
 
 import static com.google.common.base.MoreObjects.firstNonNull;
-import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_ASSIGNEE;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_ATTENTION;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_BRANCH;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_CHANGE_ID;
@@ -75,7 +74,6 @@
 import com.google.gerrit.entities.SubmitRecord.Label.Status;
 import com.google.gerrit.entities.SubmitRequirementResult;
 import com.google.gerrit.metrics.Timer0;
-import com.google.gerrit.server.AssigneeStatusUpdate;
 import com.google.gerrit.server.ReviewerByEmailSet;
 import com.google.gerrit.server.ReviewerSet;
 import com.google.gerrit.server.ReviewerStatusUpdate;
@@ -160,7 +158,6 @@
   /** Holds all updates to attention set. */
   private final List<AttentionSetUpdate> allAttentionSetUpdates;
 
-  private final List<AssigneeStatusUpdate> assigneeUpdates;
   private final List<SubmitRecord> submitRecords;
   private final ListMultimap<ObjectId, HumanComment> humanComments;
   private final List<SubmitRequirementResult> submitRequirementResults;
@@ -228,7 +225,6 @@
     reviewerUpdates = new ArrayList<>();
     latestAttentionStatus = new HashMap<>();
     allAttentionSetUpdates = new ArrayList<>();
-    assigneeUpdates = new ArrayList<>();
     submitRecords = Lists.newArrayListWithExpectedSize(1);
     allChangeMessages = new ArrayList<>();
     humanComments = MultimapBuilder.hashKeys().arrayListValues().build();
@@ -301,7 +297,6 @@
         buildReviewerUpdates(),
         ImmutableSet.copyOf(latestAttentionStatus.values()),
         allAttentionSetUpdates,
-        assigneeUpdates,
         submitRecords,
         buildAllMessages(),
         humanComments,
@@ -496,7 +491,6 @@
 
     parseHashtags(commit);
     parseAttentionSetUpdates(commit);
-    parseAssigneeUpdates(commitTimestamp, commit);
 
     parseSubmission(commit, commitTimestamp);
 
@@ -745,22 +739,6 @@
     }
   }
 
-  private void parseAssigneeUpdates(Instant ts, ChangeNotesCommit commit)
-      throws ConfigInvalidException {
-    String assigneeValue = parseOneFooter(commit, FOOTER_ASSIGNEE);
-    if (assigneeValue != null) {
-      Optional<Account.Id> parsedAssignee;
-      if (assigneeValue.equals("")) {
-        // Empty footer found, assignee deleted
-        parsedAssignee = Optional.empty();
-      } else {
-        PersonIdent ident = RawParseUtils.parsePersonIdent(assigneeValue);
-        parsedAssignee = Optional.ofNullable(parseIdent(ident));
-      }
-      assigneeUpdates.add(AssigneeStatusUpdate.create(ts, ownerId, parsedAssignee));
-    }
-  }
-
   private void parseTag(ChangeNotesCommit commit) throws ConfigInvalidException {
     tag = null;
     List<String> tagLines = commit.getFooterLineValues(FOOTER_TAG);
diff --git a/java/com/google/gerrit/server/notedb/ChangeNotesState.java b/java/com/google/gerrit/server/notedb/ChangeNotesState.java
index b0079d7..1715b43 100644
--- a/java/com/google/gerrit/server/notedb/ChangeNotesState.java
+++ b/java/com/google/gerrit/server/notedb/ChangeNotesState.java
@@ -50,12 +50,10 @@
 import com.google.gerrit.entities.converter.PatchSetProtoConverter;
 import com.google.gerrit.json.OutputFormat;
 import com.google.gerrit.proto.Protos;
-import com.google.gerrit.server.AssigneeStatusUpdate;
 import com.google.gerrit.server.ReviewerByEmailSet;
 import com.google.gerrit.server.ReviewerSet;
 import com.google.gerrit.server.ReviewerStatusUpdate;
 import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto;
-import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto.AssigneeStatusUpdateProto;
 import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto.AttentionSetUpdateProto;
 import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto.ChangeColumnsProto;
 import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto.ReviewerByEmailSetEntryProto;
@@ -68,7 +66,6 @@
 import java.time.Instant;
 import java.util.List;
 import java.util.Map;
-import java.util.Optional;
 import java.util.Set;
 import org.eclipse.jgit.lib.ObjectId;
 
@@ -124,7 +121,6 @@
       List<ReviewerStatusUpdate> reviewerUpdates,
       Set<AttentionSetUpdate> attentionSetUpdates,
       List<AttentionSetUpdate> allAttentionSetUpdates,
-      List<AssigneeStatusUpdate> assigneeUpdates,
       List<SubmitRecord> submitRecords,
       List<ChangeMessage> changeMessages,
       ListMultimap<ObjectId, HumanComment> publishedComments,
@@ -178,7 +174,6 @@
         .reviewerUpdates(reviewerUpdates)
         .attentionSet(attentionSetUpdates)
         .allAttentionSetUpdates(allAttentionSetUpdates)
-        .assigneeUpdates(assigneeUpdates)
         .submitRecords(submitRecords)
         .changeMessages(changeMessages)
         .publishedComments(publishedComments)
@@ -320,8 +315,6 @@
   /** Returns all attention set updates. */
   abstract ImmutableList<AttentionSetUpdate> allAttentionSetUpdates();
 
-  abstract ImmutableList<AssigneeStatusUpdate> assigneeUpdates();
-
   abstract ImmutableList<SubmitRecord> submitRecords();
 
   abstract ImmutableList<ChangeMessage> changeMessages();
@@ -369,9 +362,6 @@
     change.setTopic(Strings.emptyToNull(c.topic()));
     change.setLastUpdatedOn(c.lastUpdatedOn());
     change.setSubmissionId(c.submissionId());
-    if (!assigneeUpdates().isEmpty()) {
-      change.setAssignee(assigneeUpdates().get(0).currentAssignee().orElse(null));
-    }
     change.setPrivate(c.isPrivate());
     change.setWorkInProgress(c.workInProgress());
     change.setReviewStarted(c.reviewStarted());
@@ -404,7 +394,6 @@
           .reviewerUpdates(ImmutableList.of())
           .attentionSet(ImmutableSet.of())
           .allAttentionSetUpdates(ImmutableList.of())
-          .assigneeUpdates(ImmutableList.of())
           .submitRecords(ImmutableList.of())
           .changeMessages(ImmutableList.of())
           .publishedComments(ImmutableListMultimap.of())
@@ -442,8 +431,6 @@
 
     abstract Builder allAttentionSetUpdates(List<AttentionSetUpdate> attentionSetUpdates);
 
-    abstract Builder assigneeUpdates(List<AssigneeStatusUpdate> assigneeUpdates);
-
     abstract Builder submitRecords(List<SubmitRecord> submitRecords);
 
     abstract Builder changeMessages(List<ChangeMessage> changeMessages);
@@ -519,7 +506,6 @@
       object
           .allAttentionSetUpdates()
           .forEach(u -> b.addAllAttentionSetUpdate(toAttentionSetUpdateProto(u)));
-      object.assigneeUpdates().forEach(u -> b.addAssigneeUpdate(toAssigneeStatusUpdateProto(u)));
       object
           .submitRecords()
           .forEach(r -> b.addSubmitRecord(GSON.toJson(new StoredSubmitRecord(r))));
@@ -616,17 +602,6 @@
           .build();
     }
 
-    private static AssigneeStatusUpdateProto toAssigneeStatusUpdateProto(AssigneeStatusUpdate u) {
-      AssigneeStatusUpdateProto.Builder builder =
-          AssigneeStatusUpdateProto.newBuilder()
-              .setTimestampMillis(u.date().toEpochMilli())
-              .setUpdatedBy(u.updatedBy().get())
-              .setHasCurrentAssignee(u.currentAssignee().isPresent());
-
-      u.currentAssignee().ifPresent(assignee -> builder.setCurrentAssignee(assignee.get()));
-      return builder.build();
-    }
-
     @Override
     public ChangeNotesState deserialize(byte[] in) {
       ChangeNotesStateProto proto = Protos.parseUnchecked(ChangeNotesStateProto.parser(), in);
@@ -659,7 +634,6 @@
               .attentionSet(toAttentionSetUpdates(proto.getAttentionSetUpdateList()))
               .allAttentionSetUpdates(
                   toAllAttentionSetUpdates(proto.getAllAttentionSetUpdateList()))
-              .assigneeUpdates(toAssigneeStatusUpdateList(proto.getAssigneeUpdateList()))
               .submitRecords(
                   proto.getSubmitRecordList().stream()
                       .map(r -> GSON.fromJson(r, StoredSubmitRecord.class).toSubmitRecord())
@@ -783,20 +757,5 @@
       }
       return b.build();
     }
-
-    private static ImmutableList<AssigneeStatusUpdate> toAssigneeStatusUpdateList(
-        List<AssigneeStatusUpdateProto> protos) {
-      ImmutableList.Builder<AssigneeStatusUpdate> b = ImmutableList.builder();
-      for (AssigneeStatusUpdateProto proto : protos) {
-        b.add(
-            AssigneeStatusUpdate.create(
-                Instant.ofEpochMilli(proto.getTimestampMillis()),
-                Account.id(proto.getUpdatedBy()),
-                proto.getHasCurrentAssignee()
-                    ? Optional.of(Account.id(proto.getCurrentAssignee()))
-                    : Optional.empty()));
-      }
-      return b.build();
-    }
   }
 }
diff --git a/java/com/google/gerrit/server/notedb/ChangeUpdate.java b/java/com/google/gerrit/server/notedb/ChangeUpdate.java
index 5d43e28..ef62f2e 100644
--- a/java/com/google/gerrit/server/notedb/ChangeUpdate.java
+++ b/java/com/google/gerrit/server/notedb/ChangeUpdate.java
@@ -18,7 +18,6 @@
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkState;
 import static com.google.gerrit.entities.RefNames.changeMetaRef;
-import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_ASSIGNEE;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_ATTENTION;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_BRANCH;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_CHANGE_ID;
@@ -160,7 +159,6 @@
   private String commit;
   private Map<Account.Id, AttentionSetUpdate> plannedAttentionSetUpdates;
   private boolean ignoreFurtherAttentionSetUpdates;
-  private Optional<Account.Id> assignee;
   private Set<String> hashtags;
   private String changeMessage;
   private String tag;
@@ -510,15 +508,6 @@
     return attentionSetUpdatesBuilder.build();
   }
 
-  public void setAssignee(Account.Id assignee) {
-    checkArgument(assignee != null, "use removeAssignee");
-    this.assignee = Optional.of(assignee);
-  }
-
-  public void removeAssignee() {
-    this.assignee = Optional.empty();
-  }
-
   public Map<Account.Id, ReviewerStateInternal> getReviewers() {
     return reviewers;
   }
@@ -765,15 +754,6 @@
       addFooter(msg, FOOTER_COMMIT, commit);
     }
 
-    if (assignee != null) {
-      if (assignee.isPresent()) {
-        addFooter(msg, FOOTER_ASSIGNEE);
-        noteUtil.appendAccountIdIdentString(msg, assignee.get()).append('\n');
-      } else {
-        addFooter(msg, FOOTER_ASSIGNEE).append('\n');
-      }
-    }
-
     Joiner comma = Joiner.on(',');
     if (hashtags != null) {
       addFooter(msg, FOOTER_HASHTAGS, comma.join(hashtags));
@@ -1101,7 +1081,7 @@
             // remove users that are currently being removed from the attention set.
             .filter(
                 a ->
-                    plannedAttentionSetUpdates.getOrDefault(a, /*defaultValue= */ null) == null
+                    plannedAttentionSetUpdates.getOrDefault(a, /* defaultValue= */ null) == null
                         || plannedAttentionSetUpdates.get(a).operation().equals(Operation.REMOVE))
             // remove users that are still active on the change.
             .filter(a -> !isActiveOnChange(currentReviewers, a))
@@ -1173,7 +1153,6 @@
         && status == null
         && submissionId == null
         && submitRecords == null
-        && assignee == null
         && hashtags == null
         && topic == null
         && commit == null
diff --git a/java/com/google/gerrit/server/notedb/CommitRewriter.java b/java/com/google/gerrit/server/notedb/CommitRewriter.java
index a67dc07..4d71d84 100644
--- a/java/com/google/gerrit/server/notedb/CommitRewriter.java
+++ b/java/com/google/gerrit/server/notedb/CommitRewriter.java
@@ -15,7 +15,6 @@
 
 import static com.google.common.base.MoreObjects.firstNonNull;
 import static com.google.common.base.Preconditions.checkState;
-import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_ASSIGNEE;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_ATTENTION;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_LABEL;
 import static com.google.gerrit.server.notedb.ChangeNoteFooters.FOOTER_REAL_USER;
@@ -89,6 +88,7 @@
 import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.Repository;
+import org.eclipse.jgit.revwalk.FooterKey;
 import org.eclipse.jgit.revwalk.FooterLine;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevSort;
@@ -110,6 +110,10 @@
 @UsedAt(UsedAt.Project.GOOGLE)
 @Singleton
 public class CommitRewriter {
+  // Reading and Writing assignee footer no longer supported. We keep the definition here to be able
+  // to rewrite older commit messages.
+  public static final FooterKey FOOTER_ASSIGNEE = new FooterKey("Assignee");
+
   /** Options to run {@link #backfillProject}. */
   public static class RunOptions implements Serializable {
     private static final long serialVersionUID = 1L;
@@ -365,7 +369,9 @@
       }
     }
     accounts.addAll(changeNotes.getAllPastReviewers());
-    accounts.addAll(changeNotes.getPastAssignees());
+    // Change Notes class can no longer read or write assignees, we skip assignee accounts at
+    // verifyCommit stage.
+    // accounts.addAll(changeNotes.getPastAssignees());
     changeNotes
         .getAttentionSetUpdates()
         .forEach(attentionSetUpdate -> accounts.add(attentionSetUpdate.account()));
diff --git a/javatests/com/google/gerrit/server/notedb/ChangeNotesParserTest.java b/javatests/com/google/gerrit/server/notedb/ChangeNotesParserTest.java
index 4543b50..8d7066f 100644
--- a/javatests/com/google/gerrit/server/notedb/ChangeNotesParserTest.java
+++ b/javatests/com/google/gerrit/server/notedb/ChangeNotesParserTest.java
@@ -166,7 +166,8 @@
             + "Change-id: I577fb248e474018276351785930358ec0450e9f7\n"
             + "Patch-set: 1\n"
             + "Label: Label1=+1, 577fb248e474018276351785930358ec0450e9f7\n"
-            + "Label: Label1=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 2 <2@gerrit>\n"
+            + "Label: Label1=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 2"
+            + " <2@gerrit>\n"
             + "Label: Label1=0, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 2 <2@gerrit>\n"
             + "Subject: This is a test change\n");
 
@@ -183,14 +184,24 @@
     assertParseFails("Update change\n\nPatch-set: 1\nLabel: Label1=+1, \n");
     assertParseFails("Update change\n\nPatch-set: 1\nLabel: Label1=+1,\n");
     assertParseFails(
-        "Update change\n\nPatch-set: 1\nLabel: Label1=-1,  577fb248e474018276351785930358ec0450e9f7 Gerrit User 2 <2@gerrit>\n");
+        "Update change\n\n"
+            + "Patch-set: 1\n"
+            + "Label: Label1=-1,  577fb248e474018276351785930358ec0450e9f7 Gerrit User 2"
+            + " <2@gerrit>\n");
     assertParseFails(
-        "Update change\n\nPatch-set: 1\nLabel: Label1=-1,  577fb248e474018276351785930358ec0450e9f7\n");
+        "Update change\n\n"
+            + "Patch-set: 1\n"
+            + "Label: Label1=-1,  577fb248e474018276351785930358ec0450e9f7\n");
     // UUID for removals is not supported.
     assertParseFails(
-        "Update change\n\nPatch-set: 1\nLabel: -Label1, 577fb248e474018276351785930358ec0450e9f7\n");
+        "Update change\n\n"
+            + "Patch-set: 1\n"
+            + "Label: -Label1, 577fb248e474018276351785930358ec0450e9f7\n");
     assertParseFails(
-        "Update change\n\nPatch-set: 1\nLabel: -Label1, 577fb248e474018276351785930358ec0450e9f7 Other Account <2@gerrit>\n");
+        "Update change\n\n"
+            + "Patch-set: 1\n"
+            + "Label: -Label1, 577fb248e474018276351785930358ec0450e9f7 Other Account"
+            + " <2@gerrit>\n");
   }
 
   @Test
@@ -234,13 +245,20 @@
             + "Branch: refs/heads/master\n"
             + "Change-id: I577fb248e474018276351785930358ec0450e9f7\n"
             + "Patch-set: 1\n"
-            + "Copied-Label: Label2=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit>\n"
-            + "Copied-Label: Label1=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit>,Gerrit User 2 <2@gerrit>\n"
-            + "Copied-Label: Label3=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit>,Gerrit User 2 <2@gerrit> :\"tag\"\n"
-            + "Copied-Label: Label4=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit> :\"tag with characters %^#@^( *::!\"\n"
-            + "Copied-Label: Label4=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit> :\"tag with uuid delimiter , \"\n"
-            + "Copied-Label: Label4=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit>,Gerrit User 2 <2@gerrit> :\"tag with characters %^#@^( *::!\"\n"
-            + "Copied-Label: Label4=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit>,Gerrit User 2 <2@gerrit> :\"tag with uuid delimiter , \"\n"
+            + "Copied-Label: Label2=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1"
+            + " <1@gerrit>\n"
+            + "Copied-Label: Label1=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1"
+            + " <1@gerrit>,Gerrit User 2 <2@gerrit>\n"
+            + "Copied-Label: Label3=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1"
+            + " <1@gerrit>,Gerrit User 2 <2@gerrit> :\"tag\"\n"
+            + "Copied-Label: Label4=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1"
+            + " <1@gerrit> :\"tag with characters %^#@^( *::!\"\n"
+            + "Copied-Label: Label4=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1"
+            + " <1@gerrit> :\"tag with uuid delimiter , \"\n"
+            + "Copied-Label: Label4=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1"
+            + " <1@gerrit>,Gerrit User 2 <2@gerrit> :\"tag with characters %^#@^( *::!\"\n"
+            + "Copied-Label: Label4=+1, 577fb248e474018276351785930358ec0450e9f7 Gerrit User 1"
+            + " <1@gerrit>,Gerrit User 2 <2@gerrit> :\"tag with uuid delimiter , \"\n"
             + "Subject: This is a test change\n");
 
     assertParseSucceeds(
@@ -250,23 +268,34 @@
             + "Change-id: I577fb248e474018276351785930358ec0450e9f7\n"
             + "Patch-set: 1\n"
             + "Copied-Label: Label2=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit>\n"
-            + "Copied-Label: Label1=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit>,Gerrit User 2 <2@gerrit>\n"
-            + "Copied-Label: Label3=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit>,Gerrit User 2 <2@gerrit> :\"tag\"\n"
-            + "Copied-Label: Label4=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit> :\"tag with characters %^#@^( *::!\"\n"
-            + "Copied-Label: Label4=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit> :\"tag with uuid delimiter , \"\n"
-            + "Copied-Label: Label4=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit>,Gerrit User 2 <2@gerrit> :\"tag with characters %^#@^( *::!\"\n"
-            + "Copied-Label: Label4=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit>,Gerrit User 2 <2@gerrit> :\"tag with uuid delimiter , \"\n"
+            + "Copied-Label: Label1=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit>,Gerrit User 2"
+            + " <2@gerrit>\n"
+            + "Copied-Label: Label3=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit>,Gerrit User 2"
+            + " <2@gerrit> :\"tag\"\n"
+            + "Copied-Label: Label4=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit> :\"tag with"
+            + " characters %^#@^( *::!\"\n"
+            + "Copied-Label: Label4=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit> :\"tag with uuid"
+            + " delimiter , \"\n"
+            + "Copied-Label: Label4=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit>,Gerrit User 2"
+            + " <2@gerrit> :\"tag with characters %^#@^( *::!\"\n"
+            + "Copied-Label: Label4=+1, non-SHA1_UUID Gerrit User 1 <1@gerrit>,Gerrit User 2"
+            + " <2@gerrit> :\"tag with uuid delimiter , \"\n"
             + "Subject: This is a test change\n");
 
     assertParseFails("Update change\n\nPatch-set: 1\nCopied-Label: Label1=+1,\n");
     assertParseFails("Update change\n\nPatch-set: 1\nCopied-Label: Label1=+1,\n");
     assertParseFails("Update change\n\nPatch-set: 1\nCopied-Label: Label1=+1 ,\n");
     assertParseFails(
-        "Copied-Label: Label1=+1,  577fb248e474018276351785930358ec0450e9f7 Gerrit User 1 <1@gerrit>,Gerrit User 2 <2@gerrit>\n\n");
+        "Copied-Label: Label1=+1,  577fb248e474018276351785930358ec0450e9f7 Gerrit User 1"
+            + " <1@gerrit>,Gerrit User 2 <2@gerrit>\n\n");
     assertParseFails(
-        "Update change\n\nPatch-set: 1\nCopied-Label: Label1=+1, 577fb248e474018276351785930358ec0450e9f7");
+        "Update change\n\n"
+            + "Patch-set: 1\n"
+            + "Copied-Label: Label1=+1, 577fb248e474018276351785930358ec0450e9f7");
     assertParseFails(
-        "Update change\n\nPatch-set: 1\nCopied-Label: Label1=+1, 577fb248e474018276351785930358ec0450e9f7 :\"tag\"\n");
+        "Update change\n\n"
+            + "Patch-set: 1\n"
+            + "Copied-Label: Label1=+1, 577fb248e474018276351785930358ec0450e9f7 :\"tag\"\n");
 
     // UUID for removals is not supported.
     assertParseFails(
@@ -350,26 +379,6 @@
   }
 
   @Test
-  public void parseAssignee() throws Exception {
-    assertParseSucceeds(
-        "Update change\n"
-            + "\n"
-            + "Branch: refs/heads/master\n"
-            + "Change-id: I577fb248e474018276351785930358ec0450e9f7\n"
-            + "Patch-set: 1\n"
-            + "Assignee: Change Owner <1@gerrit>\n"
-            + "Subject: This is a test change\n");
-    assertParseSucceeds(
-        "Update change\n"
-            + "\n"
-            + "Branch: refs/heads/master\n"
-            + "Change-id: I577fb248e474018276351785930358ec0450e9f7\n"
-            + "Patch-set: 2\n"
-            + "Assignee:\n"
-            + "Subject: This is a test change\n");
-  }
-
-  @Test
   public void parseTopic() throws Exception {
     assertParseSucceeds(
         "Update change\n"
diff --git a/javatests/com/google/gerrit/server/notedb/ChangeNotesStateTest.java b/javatests/com/google/gerrit/server/notedb/ChangeNotesStateTest.java
index c654828..9a29230 100644
--- a/javatests/com/google/gerrit/server/notedb/ChangeNotesStateTest.java
+++ b/javatests/com/google/gerrit/server/notedb/ChangeNotesStateTest.java
@@ -45,12 +45,10 @@
 import com.google.gerrit.entities.converter.PatchSetProtoConverter;
 import com.google.gerrit.proto.Entities;
 import com.google.gerrit.proto.Protos;
-import com.google.gerrit.server.AssigneeStatusUpdate;
 import com.google.gerrit.server.ReviewerByEmailSet;
 import com.google.gerrit.server.ReviewerSet;
 import com.google.gerrit.server.ReviewerStatusUpdate;
 import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto;
-import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto.AssigneeStatusUpdateProto;
 import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto.AttentionSetUpdateProto;
 import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto.ChangeColumnsProto;
 import com.google.gerrit.server.cache.proto.Cache.ChangeNotesStateProto.ReviewerByEmailSetEntryProto;
@@ -806,37 +804,6 @@
   }
 
   @Test
-  public void serializeAssigneeUpdates() throws Exception {
-    assertRoundTrip(
-        newBuilder()
-            .assigneeUpdates(
-                ImmutableList.of(
-                    AssigneeStatusUpdate.create(
-                        Instant.ofEpochMilli(1212L),
-                        Account.id(1000),
-                        Optional.of(Account.id(2001))),
-                    AssigneeStatusUpdate.create(
-                        Instant.ofEpochMilli(3434L), Account.id(1000), Optional.empty())))
-            .build(),
-        ChangeNotesStateProto.newBuilder()
-            .setMetaId(SHA_BYTES)
-            .setChangeId(ID.get())
-            .setColumns(colsProto)
-            .addAssigneeUpdate(
-                AssigneeStatusUpdateProto.newBuilder()
-                    .setTimestampMillis(1212L)
-                    .setUpdatedBy(1000)
-                    .setCurrentAssignee(2001)
-                    .setHasCurrentAssignee(true))
-            .addAssigneeUpdate(
-                AssigneeStatusUpdateProto.newBuilder()
-                    .setTimestampMillis(3434L)
-                    .setUpdatedBy(1000)
-                    .setHasCurrentAssignee(false))
-            .build());
-  }
-
-  @Test
   public void serializeSubmitRecords() throws Exception {
     SubmitRecord sr1 = new SubmitRecord();
     sr1.status = SubmitRecord.Status.OK;
@@ -971,9 +938,6 @@
                 .put(
                     "allAttentionSetUpdates",
                     new TypeLiteral<ImmutableList<AttentionSetUpdate>>() {}.getType())
-                .put(
-                    "assigneeUpdates",
-                    new TypeLiteral<ImmutableList<AssigneeStatusUpdate>>() {}.getType())
                 .put("submitRecords", new TypeLiteral<ImmutableList<SubmitRecord>>() {}.getType())
                 .put("changeMessages", new TypeLiteral<ImmutableList<ChangeMessage>>() {}.getType())
                 .put(
@@ -1088,19 +1052,6 @@
   }
 
   @Test
-  public void assigneeStatusUpdateMethods() throws Exception {
-    assertThatSerializedClass(AssigneeStatusUpdate.class)
-        .hasAutoValueMethods(
-            ImmutableMap.of(
-                "date",
-                Instant.class,
-                "updatedBy",
-                Account.Id.class,
-                "currentAssignee",
-                new TypeLiteral<Optional<Account.Id>>() {}.getType()));
-  }
-
-  @Test
   public void submitRecordFields() throws Exception {
     assertThatSerializedClass(SubmitRecord.class)
         .hasFields(
diff --git a/javatests/com/google/gerrit/server/notedb/ChangeNotesTest.java b/javatests/com/google/gerrit/server/notedb/ChangeNotesTest.java
index 9cd002e..cf739f6 100644
--- a/javatests/com/google/gerrit/server/notedb/ChangeNotesTest.java
+++ b/javatests/com/google/gerrit/server/notedb/ChangeNotesTest.java
@@ -53,7 +53,6 @@
 import com.google.gerrit.entities.SubmissionId;
 import com.google.gerrit.entities.SubmitRecord;
 import com.google.gerrit.exceptions.StorageException;
-import com.google.gerrit.server.AssigneeStatusUpdate;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.ReviewerSet;
@@ -1474,91 +1473,6 @@
   }
 
   @Test
-  public void assigneeCommit() throws Exception {
-    Change c = newChange();
-    ChangeUpdate update = newUpdate(c, changeOwner);
-    update.setAssignee(otherUserId);
-    ObjectId result = update.commit();
-    assertThat(result).isNotNull();
-    try (RevWalk rw = new RevWalk(repo)) {
-      RevCommit commit = rw.parseCommit(update.getResult());
-      rw.parseBody(commit);
-      String strIdent = "Gerrit User " + otherUserId + " <" + otherUserId + "@" + serverId + ">";
-      assertThat(commit.getFullMessage()).contains("Assignee: " + strIdent);
-    }
-  }
-
-  @Test
-  public void assigneeChangeNotes() throws Exception {
-    Change c = newChange();
-    ChangeUpdate update = newUpdate(c, changeOwner);
-    update.setAssignee(otherUserId);
-    update.commit();
-
-    ChangeNotes notes = newNotes(c);
-    assertThat(notes.getChange().getAssignee()).isEqualTo(otherUserId);
-
-    update = newUpdate(c, changeOwner);
-    update.setAssignee(changeOwner.getAccountId());
-    update.commit();
-
-    notes = newNotes(c);
-    assertThat(notes.getChange().getAssignee()).isEqualTo(changeOwner.getAccountId());
-  }
-
-  @Test
-  public void pastAssigneesChangeNotes() throws Exception {
-    Change c = newChange();
-    ChangeUpdate update = newUpdate(c, changeOwner);
-    update.setAssignee(otherUserId);
-    update.commit();
-
-    update = newUpdate(c, changeOwner);
-    update.setAssignee(changeOwner.getAccountId());
-    update.commit();
-
-    update = newUpdate(c, changeOwner);
-    update.setAssignee(otherUserId);
-    update.commit();
-
-    update = newUpdate(c, changeOwner);
-    update.removeAssignee();
-    update.commit();
-
-    ChangeNotes notes = newNotes(c);
-    assertThat(notes.getPastAssignees()).hasSize(2);
-  }
-
-  @Test
-  public void assigneeStatusUpdateChangeNotes() throws Exception {
-    Change c = newChange();
-    ChangeUpdate update = newUpdate(c, otherUser);
-    update.setAssignee(otherUserId);
-    update.commit();
-
-    update = newUpdate(c, changeOwner);
-    update.removeAssignee();
-    update.commit();
-
-    update = newUpdate(c, changeOwner);
-    update.setAssignee(changeOwner.getAccountId());
-    update.commit();
-
-    update = newUpdate(c, changeOwner);
-    update.setAssignee(otherUserId);
-    update.commit();
-
-    ChangeNotes notes = newNotes(c);
-    ImmutableList<AssigneeStatusUpdate> statusUpdates = notes.getAssigneeUpdates();
-    assertThat(statusUpdates).hasSize(4);
-    assertThat(statusUpdates.get(3).updatedBy()).isEqualTo(otherUserId);
-    assertThat(statusUpdates.get(3).currentAssignee()).hasValue(otherUserId);
-    assertThat(statusUpdates.get(2).currentAssignee()).isEmpty();
-    assertThat(statusUpdates.get(1).currentAssignee()).hasValue(changeOwner.getAccountId());
-    assertThat(statusUpdates.get(0).currentAssignee()).hasValue(otherUserId);
-  }
-
-  @Test
   public void hashtagCommit() throws Exception {
     Change c = newChange();
     ChangeUpdate update = newUpdate(c, changeOwner);
diff --git a/javatests/com/google/gerrit/server/notedb/CommitRewriterTest.java b/javatests/com/google/gerrit/server/notedb/CommitRewriterTest.java
index 527e78e..4f4911a 100644
--- a/javatests/com/google/gerrit/server/notedb/CommitRewriterTest.java
+++ b/javatests/com/google/gerrit/server/notedb/CommitRewriterTest.java
@@ -214,37 +214,37 @@
   @Test
   public void maxRefsToUpdate_coversAllInvalid_inMultipleBatches() throws Exception {
     testMaxRefsToUpdate(
-        /*numberOfInvalidChanges=*/ 11,
-        /*numberOfValidChanges=*/ 9,
-        /*maxRefsToUpdate=*/ 12,
-        /*maxRefsInBatch=*/ 2);
+        /* numberOfInvalidChanges= */ 11,
+        /* numberOfValidChanges= */ 9,
+        /* maxRefsToUpdate= */ 12,
+        /* maxRefsInBatch= */ 2);
   }
 
   @Test
   public void maxRefsToUpdate_coversAllInvalid_inSingleBatch() throws Exception {
     testMaxRefsToUpdate(
-        /*numberOfInvalidChanges=*/ 11,
-        /*numberOfValidChanges=*/ 9,
-        /*maxRefsToUpdate=*/ 12,
-        /*maxRefsInBatch=*/ 12);
+        /* numberOfInvalidChanges= */ 11,
+        /* numberOfValidChanges= */ 9,
+        /* maxRefsToUpdate= */ 12,
+        /* maxRefsInBatch= */ 12);
   }
 
   @Test
   public void moreInvalidRefs_thenMaxRefsToUpdate_inMultipleBatches() throws Exception {
     testMaxRefsToUpdate(
-        /*numberOfInvalidChanges=*/ 11,
-        /*numberOfValidChanges=*/ 9,
-        /*maxRefsToUpdate=*/ 10,
-        /*maxRefsInBatch=*/ 2);
+        /* numberOfInvalidChanges= */ 11,
+        /* numberOfValidChanges= */ 9,
+        /* maxRefsToUpdate= */ 10,
+        /* maxRefsInBatch= */ 2);
   }
 
   @Test
   public void moreInvalidRefs_thenMaxRefsToUpdate_inSingleBatch() throws Exception {
     testMaxRefsToUpdate(
-        /*numberOfInvalidChanges=*/ 11,
-        /*numberOfValidChanges=*/ 9,
-        /*maxRefsToUpdate=*/ 10,
-        /*maxRefsInBatch=*/ 10);
+        /* numberOfInvalidChanges= */ 11,
+        /* numberOfValidChanges= */ 9,
+        /* maxRefsToUpdate= */ 10,
+        /* maxRefsInBatch= */ 10);
   }
 
   private void testMaxRefsToUpdate(
@@ -333,7 +333,7 @@
     RevCommit invalidUpdateCommit =
         writeUpdate(
             RefNames.changeMetaRef(c.getId()),
-            getChangeUpdateBody(c, /*changeMessage=*/ null),
+            getChangeUpdateBody(c, /* changeMessage= */ null),
             invalidAuthorIdent);
     ChangeUpdate validUpdate = newUpdate(c, changeOwner);
     validUpdate.setChangeMessage("verification from jenkins");
@@ -472,7 +472,8 @@
                     // valid change message that should not be overwritten
                     getChangeUpdateBody(
                         c,
-                        "Removed cc <GERRIT_ACCOUNT_2> with the following votes:\n\n * Code-Review+2 by <GERRIT_ACCOUNT_2>",
+                        "Removed cc <GERRIT_ACCOUNT_2> with the following votes:\n\n"
+                            + " * Code-Review+2 by <GERRIT_ACCOUNT_2>",
                         "CC: " + reviewerIdentToFix),
                     getAuthorIdent(otherUser.getAccount())))
             .add(
@@ -677,7 +678,7 @@
                     RefNames.changeMetaRef(c.getId()),
                     getChangeUpdateBody(
                         c,
-                        /*changeMessage=*/ null,
+                        /* changeMessage= */ null,
                         "Label: -Verified " + approverIdentToFix,
                         "Label: Custom-Label-1=-1 " + approverIdentToFix,
                         "Label: Verified=+1",
@@ -690,7 +691,7 @@
                     RefNames.changeMetaRef(c.getId()),
                     getChangeUpdateBody(
                         c,
-                        /*changeMessage=*/ null,
+                        /* changeMessage= */ null,
                         "Label: -Verified " + changeOwnerIdentToFix,
                         "Label: Custom-Label-1=+1"),
                     getAuthorIdent(otherUser.getAccount())))
@@ -812,7 +813,7 @@
                     RefNames.changeMetaRef(c.getId()),
                     getChangeUpdateBody(
                         c,
-                        /*changeMessage=*/ "Removed Code-Review+2 by " + otherUser.getNameEmail(),
+                        /* changeMessage= */ "Removed Code-Review+2 by " + otherUser.getNameEmail(),
                         "Label: -Code-Review " + approverIdentToFix),
                     getAuthorIdent(changeOwner.getAccount())))
             .add(
@@ -820,7 +821,8 @@
                     RefNames.changeMetaRef(c.getId()),
                     getChangeUpdateBody(
                         c,
-                        /*changeMessage=*/ "Removed Custom-Label-1 by " + otherUser.getNameEmail(),
+                        /* changeMessage= */ "Removed Custom-Label-1 by "
+                            + otherUser.getNameEmail(),
                         "Label: -Custom-Label " + getValidIdentAsString(otherUser.getAccount())),
                     getAuthorIdent(changeOwner.getAccount())))
             .add(
@@ -828,7 +830,7 @@
                     RefNames.changeMetaRef(c.getId()),
                     getChangeUpdateBody(
                         c,
-                        /*changeMessage=*/ "Removed Verified+2 by " + changeOwner.getNameEmail(),
+                        /* changeMessage= */ "Removed Verified+2 by " + changeOwner.getNameEmail(),
                         "Label: -Verified"),
                     getAuthorIdent(changeOwner.getAccount())))
             .build();
@@ -928,7 +930,7 @@
         RefNames.changeMetaRef(c.getId()),
         getChangeUpdateBody(
             c,
-            /*changeMessage=*/ "Removed Verified+2 by " + otherUser.getNameEmail(),
+            /* changeMessage= */ "Removed Verified+2 by " + otherUser.getNameEmail(),
             "Label: -Verified"),
         invalidAuthorIdent);
 
@@ -961,19 +963,19 @@
         RefNames.changeMetaRef(c.getId()),
 
         // Even though footer is missing, accounts are matched among the account in change updates.
-        getChangeUpdateBody(c, /*changeMessage=*/ "Removed Verified-1 by Other Account (0002)"),
+        getChangeUpdateBody(c, /* changeMessage= */ "Removed Verified-1 by Other Account (0002)"),
         getAuthorIdent(changeOwner.getAccount()));
 
     writeUpdate(
         RefNames.changeMetaRef(c.getId()),
         getChangeUpdateBody(
-            c, /*changeMessage=*/ "Removed Verified+2 by " + changeOwner.getNameEmail()),
+            c, /* changeMessage= */ "Removed Verified+2 by " + changeOwner.getNameEmail()),
         getAuthorIdent(changeOwner.getAccount()));
 
     // No rewrite for default
     writeUpdate(
         RefNames.changeMetaRef(c.getId()),
-        getChangeUpdateBody(c, /*changeMessage=*/ "Removed Verified+2 by Gerrit Account"),
+        getChangeUpdateBody(c, /* changeMessage= */ "Removed Verified+2 by Gerrit Account"),
         getAuthorIdent(changeOwner.getAccount()));
 
     RunOptions options = new RunOptions();
@@ -1006,7 +1008,8 @@
     writeUpdate(
         RefNames.changeMetaRef(c.getId()),
         getChangeUpdateBody(
-            c, /*changeMessage=*/ "Removed Verified+2 by Renamed Change Owner <change@owner.com>"),
+            c,
+            /* changeMessage= */ "Removed Verified+2 by Renamed Change Owner <change@owner.com>"),
         getAuthorIdent(changeOwner.getAccount()));
 
     RunOptions options = new RunOptions();
@@ -1035,7 +1038,7 @@
     approvalUpdate.commit();
     writeUpdate(
         RefNames.changeMetaRef(c.getId()),
-        getChangeUpdateBody(c, /*changeMessage=*/ "Removed Verified+2 by Change Owner"),
+        getChangeUpdateBody(c, /* changeMessage= */ "Removed Verified+2 by Change Owner"),
         getAuthorIdent(changeOwner.getAccount()));
 
     RunOptions options = new RunOptions();
@@ -1072,17 +1075,17 @@
     writeUpdate(
         RefNames.changeMetaRef(c.getId()),
         getChangeUpdateBody(
-            c, /*changeMessage=*/ "Removed Verified+2 by Change Owner <other@test.com>"),
+            c, /* changeMessage= */ "Removed Verified+2 by Change Owner <other@test.com>"),
         getAuthorIdent(changeOwner.getAccount()));
     writeUpdate(
         RefNames.changeMetaRef(c.getId()),
         getChangeUpdateBody(
-            c, /*changeMessage=*/ "Removed Verified+2 by Change Owner <change@owner.com>"),
+            c, /* changeMessage= */ "Removed Verified+2 by Change Owner <change@owner.com>"),
         getAuthorIdent(changeOwner.getAccount()));
     writeUpdate(
         RefNames.changeMetaRef(c.getId()),
         getChangeUpdateBody(
-            c, /*changeMessage=*/ "Removed Verified-1 by Change Owner <other@test.com>"),
+            c, /* changeMessage= */ "Removed Verified-1 by Change Owner <other@test.com>"),
         getAuthorIdent(changeOwner.getAccount()));
 
     RunOptions options = new RunOptions();
@@ -1121,7 +1124,7 @@
         // Even though footer is missing, accounts are matched among the account in change updates.
         getChangeUpdateBody(
             c,
-            /*changeMessage=*/ "Removed the following votes:\n"
+            /* changeMessage= */ "Removed the following votes:\n"
                 + String.format("* Verified-1 by %s\n", otherUser.getNameEmail())),
         getAuthorIdent(changeOwner.getAccount()));
 
@@ -1129,7 +1132,7 @@
         RefNames.changeMetaRef(c.getId()),
         getChangeUpdateBody(
             c,
-            /*changeMessage=*/ "Removed the following votes:\n"
+            /* changeMessage= */ "Removed the following votes:\n"
                 + String.format("* Verified+2 by %s\n", changeOwner.getNameEmail())
                 + String.format("* Verified-1 by %s\n", changeOwner.getNameEmail())
                 + String.format("* Code-Review by %s\n", otherUser.getNameEmail())),
@@ -1140,7 +1143,7 @@
         RefNames.changeMetaRef(c.getId()),
         getChangeUpdateBody(
             c,
-            /*changeMessage=*/ "Removed the following votes:\n"
+            /* changeMessage= */ "Removed the following votes:\n"
                 + "* Verified+2 by Gerrit Account\n"
                 + "* Verified-1 by <GERRIT_ACCOUNT_2>\n"),
         getAuthorIdent(changeOwner.getAccount()));
@@ -1200,7 +1203,7 @@
             RefNames.changeMetaRef(c.getId()),
             getChangeUpdateBody(
                 c,
-                /*changeMessage=*/ null,
+                /* changeMessage= */ null,
                 // Only 'person_ident' fix is required
                 "Attention: "
                     + gson.toJson(
@@ -1354,27 +1357,51 @@
     assertThat(commitHistoryDiff.get(0))
         .isEqualTo(
             "@@ -8 +8 @@\n"
-                + "-Attention: {\"person_ident\":\"Gerrit User 2 \\u003c2@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Added by Other Account using the hovercard menu\"}\n"
-                + "+Attention: {\"person_ident\":\"Gerrit User 2 \\u003c2@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Added by someone using the hovercard menu\"}\n");
+                + "-Attention: {\"person_ident\":\"Gerrit User 2"
+                + " \\u003c2@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Added by Other"
+                + " Account using the hovercard menu\"}\n"
+                + "+Attention: {\"person_ident\":\"Gerrit User 2"
+                + " \\u003c2@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Added by someone"
+                + " using the hovercard menu\"}\n");
     assertThat(Arrays.asList(commitHistoryDiff.get(1).split("\n")))
         .containsExactly(
             "@@ -7,2 +7,2 @@",
-            "-Attention: {\"person_ident\":\"Gerrit User 1 \\u003c1@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Other Account replied on the change\"}",
-            "-Attention: {\"person_ident\":\"Gerrit User 2 \\u003c2@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Removed by Other Account using the hovercard menu\"}",
-            "+Attention: {\"person_ident\":\"Gerrit User 1 \\u003c1@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Someone replied on the change\"}",
-            "+Attention: {\"person_ident\":\"Gerrit User 2 \\u003c2@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Removed by someone using the hovercard menu\"}");
+            "-Attention: {\"person_ident\":\"Gerrit User 1"
+                + " \\u003c1@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Other Account"
+                + " replied on the change\"}",
+            "-Attention: {\"person_ident\":\"Gerrit User 2"
+                + " \\u003c2@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Removed by Other"
+                + " Account using the hovercard menu\"}",
+            "+Attention: {\"person_ident\":\"Gerrit User 1"
+                + " \\u003c1@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Someone replied on"
+                + " the change\"}",
+            "+Attention: {\"person_ident\":\"Gerrit User 2"
+                + " \\u003c2@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Removed by"
+                + " someone using the hovercard menu\"}");
     assertThat(Arrays.asList(commitHistoryDiff.get(2).split("\n")))
         .containsExactly(
             "@@ -7,2 +7,2 @@",
-            "-Attention: {\"person_ident\":\"Other Account \\u003c2@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Added by someone using the hovercard menu\"}",
-            "-Attention: {\"person_ident\":\"Change Owner \\u003c1@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Other Account replied on the change\"}",
-            "+Attention: {\"person_ident\":\"Gerrit User 2 \\u003c2@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Added by someone using the hovercard menu\"}",
-            "+Attention: {\"person_ident\":\"Gerrit User 1 \\u003c1@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Someone replied on the change\"}");
+            "-Attention: {\"person_ident\":\"Other Account"
+                + " \\u003c2@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Added by someone"
+                + " using the hovercard menu\"}",
+            "-Attention: {\"person_ident\":\"Change Owner"
+                + " \\u003c1@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Other Account"
+                + " replied on the change\"}",
+            "+Attention: {\"person_ident\":\"Gerrit User 2"
+                + " \\u003c2@gerrit\\u003e\",\"operation\":\"ADD\",\"reason\":\"Added by someone"
+                + " using the hovercard menu\"}",
+            "+Attention: {\"person_ident\":\"Gerrit User 1"
+                + " \\u003c1@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Someone replied"
+                + " on the change\"}");
     assertThat(commitHistoryDiff.get(3))
         .isEqualTo(
             "@@ -7 +7 @@\n"
-                + "-Attention: {\"person_ident\":\"Gerrit User 1 \\u003c1@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Removed by Other Account by clicking the attention icon\"}\n"
-                + "+Attention: {\"person_ident\":\"Gerrit User 1 \\u003c1@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Removed by someone by clicking the attention icon\"}\n");
+                + "-Attention: {\"person_ident\":\"Gerrit User 1"
+                + " \\u003c1@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Removed by Other"
+                + " Account by clicking the attention icon\"}\n"
+                + "+Attention: {\"person_ident\":\"Gerrit User 1"
+                + " \\u003c1@gerrit\\u003e\",\"operation\":\"REMOVE\",\"reason\":\"Removed by"
+                + " someone by clicking the attention icon\"}\n");
     BackfillResult secondRunResult = rewriter.backfillProject(project, repo, options);
     assertThat(secondRunResult.fixedRefDiff.keySet()).isEmpty();
     assertThat(secondRunResult.refsFailedToFix).isEmpty();
@@ -1483,13 +1510,15 @@
     commitsToFix.add(invalidCherryPickedMessageUpdate.commit());
     ChangeUpdate invalidRebasedMessageUpdate = newUpdate(c, changeOwner);
     invalidRebasedMessageUpdate.setChangeMessage(
-        "Change has been successfully rebased and submitted as e40dc1a50dc7f457a37579e2755374f3e1a5413b by "
+        "Change has been successfully rebased and submitted as"
+            + " e40dc1a50dc7f457a37579e2755374f3e1a5413b by "
             + changeOwner.getName());
 
     commitsToFix.add(invalidRebasedMessageUpdate.commit());
     ChangeUpdate validSubmitMessageUpdate = newUpdate(c, changeOwner);
     validSubmitMessageUpdate.setChangeMessage(
-        "Change has been successfully rebased and submitted as e40dc1a50dc7f457a37579e2755374f3e1a5413b");
+        "Change has been successfully rebased and submitted as"
+            + " e40dc1a50dc7f457a37579e2755374f3e1a5413b");
     validSubmitMessageUpdate.commit();
 
     Ref metaRefBeforeRewrite = repo.exactRef(RefNames.changeMetaRef(c.getId()));
@@ -1512,15 +1541,21 @@
     assertThat(changeMessages(notesBeforeRewrite))
         .containsExactly(
             "Change has been successfully merged by Change Owner",
-            "Change has been successfully cherry-picked as e40dc1a50dc7f457a37579e2755374f3e1a5413b by Change Owner",
-            "Change has been successfully rebased and submitted as e40dc1a50dc7f457a37579e2755374f3e1a5413b by Change Owner",
-            "Change has been successfully rebased and submitted as e40dc1a50dc7f457a37579e2755374f3e1a5413b");
+            "Change has been successfully cherry-picked as e40dc1a50dc7f457a37579e2755374f3e1a5413b"
+                + " by Change Owner",
+            "Change has been successfully rebased and submitted as"
+                + " e40dc1a50dc7f457a37579e2755374f3e1a5413b by Change Owner",
+            "Change has been successfully rebased and submitted as"
+                + " e40dc1a50dc7f457a37579e2755374f3e1a5413b");
     assertThat(changeMessages(notesAfterRewrite))
         .containsExactly(
             "Change has been successfully merged",
-            "Change has been successfully cherry-picked as e40dc1a50dc7f457a37579e2755374f3e1a5413b",
-            "Change has been successfully rebased and submitted as e40dc1a50dc7f457a37579e2755374f3e1a5413b",
-            "Change has been successfully rebased and submitted as e40dc1a50dc7f457a37579e2755374f3e1a5413b");
+            "Change has been successfully cherry-picked as"
+                + " e40dc1a50dc7f457a37579e2755374f3e1a5413b",
+            "Change has been successfully rebased and submitted as"
+                + " e40dc1a50dc7f457a37579e2755374f3e1a5413b",
+            "Change has been successfully rebased and submitted as"
+                + " e40dc1a50dc7f457a37579e2755374f3e1a5413b");
 
     Ref metaRefAfterRewrite = repo.exactRef(RefNames.changeMetaRef(c.getId()));
     assertThat(metaRefAfterRewrite.getObjectId()).isNotEqualTo(metaRefBeforeRewrite.getObjectId());
@@ -1536,11 +1571,15 @@
                 + "-Change has been successfully merged by Change Owner\n"
                 + "+Change has been successfully merged\n",
             "@@ -6 +6 @@\n"
-                + "-Change has been successfully cherry-picked as e40dc1a50dc7f457a37579e2755374f3e1a5413b by Change Owner\n"
-                + "+Change has been successfully cherry-picked as e40dc1a50dc7f457a37579e2755374f3e1a5413b\n",
+                + "-Change has been successfully cherry-picked as"
+                + " e40dc1a50dc7f457a37579e2755374f3e1a5413b by Change Owner\n"
+                + "+Change has been successfully cherry-picked as"
+                + " e40dc1a50dc7f457a37579e2755374f3e1a5413b\n",
             "@@ -6 +6 @@\n"
-                + "-Change has been successfully rebased and submitted as e40dc1a50dc7f457a37579e2755374f3e1a5413b by Change Owner\n"
-                + "+Change has been successfully rebased and submitted as e40dc1a50dc7f457a37579e2755374f3e1a5413b\n");
+                + "-Change has been successfully rebased and submitted as"
+                + " e40dc1a50dc7f457a37579e2755374f3e1a5413b by Change Owner\n"
+                + "+Change has been successfully rebased and submitted as"
+                + " e40dc1a50dc7f457a37579e2755374f3e1a5413b\n");
     BackfillResult secondRunResult = rewriter.backfillProject(project, repo, options);
     assertThat(secondRunResult.fixedRefDiff.keySet()).isEmpty();
     assertThat(secondRunResult.refsFailedToFix).isEmpty();
@@ -1610,7 +1649,7 @@
             RefNames.changeMetaRef(c.getId()),
             getChangeUpdateBody(
                 c,
-                /*changeMessage=*/ null,
+                /* changeMessage= */ null,
                 "Label: SUBM=+1",
                 "Submission-id: 5271-1496917120975-10a10df9",
                 "Submitted-with: NOT_READY",
@@ -1876,59 +1915,72 @@
     ChangeUpdate invalidOnReviewUpdate = newUpdate(c, changeOwner);
     invalidOnReviewUpdate.setChangeMessage(
         "Patch Set 1: Any-Label+2 Other-Label+2 Code-Review+2\n\n"
-            + "By voting Code-Review+2 the following files are now code-owner approved by Change Owner:\n"
+            + "By voting Code-Review+2 the following files are now code-owner approved by Change"
+            + " Owner:\n"
             + "   * file1.java\n"
             + "   * file2.ts\n"
-            + "By voting Any-Label+2 the code-owners submit requirement is overridden by Change Owner\n"
-            + "By voting Other-Label+2 the code-owners submit requirement is still overridden by Change Owner\n");
+            + "By voting Any-Label+2 the code-owners submit requirement is overridden by Change"
+            + " Owner\n"
+            + "By voting Other-Label+2 the code-owners submit requirement is still overridden by"
+            + " Change Owner\n");
     commitsToFix.add(invalidOnReviewUpdate.commit());
 
     ChangeUpdate invalidOnReviewUpdateAnyOrder = newUpdate(c, changeOwner);
     invalidOnReviewUpdateAnyOrder.setChangeMessage(
         "Patch Set 1: Any-Label+2 Other-Label+2 Code-Review+2\n\n"
-            + "By voting Any-Label+2 the code-owners submit requirement is overridden by Change Owner\n"
-            + "By voting Other-Label+2 the code-owners submit requirement is still overridden by Change Owner\n"
-            + "By voting Code-Review+2 the following files are now code-owner approved by Change Owner:\n"
+            + "By voting Any-Label+2 the code-owners submit requirement is overridden by Change"
+            + " Owner\n"
+            + "By voting Other-Label+2 the code-owners submit requirement is still overridden by"
+            + " Change Owner\n"
+            + "By voting Code-Review+2 the following files are now code-owner approved by Change"
+            + " Owner:\n"
             + "   * file1.java\n"
             + "   * file2.ts\n");
     commitsToFix.add(invalidOnReviewUpdateAnyOrder.commit());
     ChangeUpdate invalidOnApprovalUpdate = newUpdate(c, otherUser);
     invalidOnApprovalUpdate.setChangeMessage(
         "Patch Set 1: -Code-Review\n\n"
-            + "By removing the Code-Review+2 vote the following files are no longer explicitly code-owner approved by Other Account:\n"
+            + "By removing the Code-Review+2 vote the following files are no longer explicitly"
+            + " code-owner approved by Other Account:\n"
             + "   * file1.java\n"
             + "   * file2.ts\n"
-            + "\nThe listed files are still implicitly approved by Other Account.\n");
+            + "\n"
+            + "The listed files are still implicitly approved by Other Account.\n");
     commitsToFix.add(invalidOnApprovalUpdate.commit());
 
     ChangeUpdate invalidOnOverrideUpdate = newUpdate(c, changeOwner);
     invalidOnOverrideUpdate.setChangeMessage(
         "Patch Set 1: -Owners-Override\n\n"
             + "(1 comment)\n\n"
-            + "By removing the Owners-Override+1 vote the code-owners submit requirement is no longer overridden by Change Owner\n");
+            + "By removing the Owners-Override+1 vote the code-owners submit requirement is no"
+            + " longer overridden by Change Owner\n");
 
     commitsToFix.add(invalidOnOverrideUpdate.commit());
 
     ChangeUpdate partiallyValidOnReviewUpdate = newUpdate(c, changeOwner);
     partiallyValidOnReviewUpdate.setChangeMessage(
         "Patch Set 1: Any-Label+2 Code-Review+2\n\n"
-            + "By voting Code-Review+2 the following files are now code-owner approved by <GERRIT_ACCOUNT_1>:\n"
+            + "By voting Code-Review+2 the following files are now code-owner approved by"
+            + " <GERRIT_ACCOUNT_1>:\n"
             + "   * file1.java\n"
             + "   * file2.ts\n"
-            + "By voting Any-Label+2 the code-owners submit requirement is overridden by Change Owner\n");
+            + "By voting Any-Label+2 the code-owners submit requirement is overridden by Change"
+            + " Owner\n");
     commitsToFix.add(partiallyValidOnReviewUpdate.commit());
 
     ChangeUpdate validOnApprovalUpdate = newUpdate(c, changeOwner);
     validOnApprovalUpdate.setChangeMessage(
         "Patch Set 1: Code-Review-2\n\n"
-            + "By voting Code-Review-2 the following files are no longer explicitly code-owner approved by <GERRIT_ACCOUNT_1>:\n"
+            + "By voting Code-Review-2 the following files are no longer explicitly code-owner"
+            + " approved by <GERRIT_ACCOUNT_1>:\n"
             + "   * file4.java\n");
     validOnApprovalUpdate.commit();
 
     ChangeUpdate validOnOverrideUpdate = newUpdate(c, changeOwner);
     validOnOverrideUpdate.setChangeMessage(
         "Patch Set 1: Owners-Override+1\n\n"
-            + "By voting Owners-Override+1 the code-owners submit requirement is still overridden by <GERRIT_ACCOUNT_1>\n");
+            + "By voting Owners-Override+1 the code-owners submit requirement is still overridden"
+            + " by <GERRIT_ACCOUNT_1>\n");
     validOnOverrideUpdate.commit();
 
     Ref metaRefBeforeRewrite = repo.exactRef(RefNames.changeMetaRef(c.getId()));
@@ -1952,39 +2004,52 @@
     assertThat(changeMessages(notesAfterRewrite))
         .containsExactly(
             "Patch Set 1: Any-Label+2 Other-Label+2 Code-Review+2\n\n"
-                + "By voting Code-Review+2 the following files are now code-owner approved by <GERRIT_ACCOUNT_1>:\n"
+                + "By voting Code-Review+2 the following files are now code-owner approved by"
+                + " <GERRIT_ACCOUNT_1>:\n"
                 + "   * file1.java\n"
                 + "   * file2.ts\n"
-                + "By voting Any-Label+2 the code-owners submit requirement is overridden by <GERRIT_ACCOUNT_1>\n"
-                + "By voting Other-Label+2 the code-owners submit requirement is still overridden by <GERRIT_ACCOUNT_1>\n",
+                + "By voting Any-Label+2 the code-owners submit requirement is overridden by"
+                + " <GERRIT_ACCOUNT_1>\n"
+                + "By voting Other-Label+2 the code-owners submit requirement is still overridden"
+                + " by <GERRIT_ACCOUNT_1>\n",
             "Patch Set 1: Any-Label+2 Other-Label+2 Code-Review+2\n\n"
-                + "By voting Any-Label+2 the code-owners submit requirement is overridden by <GERRIT_ACCOUNT_1>\n"
-                + "By voting Other-Label+2 the code-owners submit requirement is still overridden by <GERRIT_ACCOUNT_1>\n"
-                + "By voting Code-Review+2 the following files are now code-owner approved by <GERRIT_ACCOUNT_1>:\n"
+                + "By voting Any-Label+2 the code-owners submit requirement is overridden by"
+                + " <GERRIT_ACCOUNT_1>\n"
+                + "By voting Other-Label+2 the code-owners submit requirement is still overridden"
+                + " by <GERRIT_ACCOUNT_1>\n"
+                + "By voting Code-Review+2 the following files are now code-owner approved by"
+                + " <GERRIT_ACCOUNT_1>:\n"
                 + "   * file1.java\n"
                 + "   * file2.ts\n",
             "Patch Set 1: -Code-Review\n"
                 + "\n"
-                + "By removing the Code-Review+2 vote the following files are no longer explicitly code-owner approved by <GERRIT_ACCOUNT_2>:\n"
+                + "By removing the Code-Review+2 vote the following files are no longer explicitly"
+                + " code-owner approved by <GERRIT_ACCOUNT_2>:\n"
                 + "   * file1.java\n"
                 + "   * file2.ts\n"
-                + "\nThe listed files are still implicitly approved by <GERRIT_ACCOUNT_2>.\n",
+                + "\n"
+                + "The listed files are still implicitly approved by <GERRIT_ACCOUNT_2>.\n",
             "Patch Set 1: -Owners-Override\n"
                 + "\n"
                 + "(1 comment)\n"
                 + "\n"
-                + "By removing the Owners-Override+1 vote the code-owners submit requirement is no longer overridden by <GERRIT_ACCOUNT_1>\n",
+                + "By removing the Owners-Override+1 vote the code-owners submit requirement is no"
+                + " longer overridden by <GERRIT_ACCOUNT_1>\n",
             "Patch Set 1: Any-Label+2 Code-Review+2\n\n"
-                + "By voting Code-Review+2 the following files are now code-owner approved by <GERRIT_ACCOUNT_1>:\n"
+                + "By voting Code-Review+2 the following files are now code-owner approved by"
+                + " <GERRIT_ACCOUNT_1>:\n"
                 + "   * file1.java\n"
                 + "   * file2.ts\n"
-                + "By voting Any-Label+2 the code-owners submit requirement is overridden by <GERRIT_ACCOUNT_1>\n",
+                + "By voting Any-Label+2 the code-owners submit requirement is overridden by"
+                + " <GERRIT_ACCOUNT_1>\n",
             "Patch Set 1: Code-Review-2\n\n"
-                + "By voting Code-Review-2 the following files are no longer explicitly code-owner approved by <GERRIT_ACCOUNT_1>:\n"
+                + "By voting Code-Review-2 the following files are no longer explicitly code-owner"
+                + " approved by <GERRIT_ACCOUNT_1>:\n"
                 + "   * file4.java\n",
             "Patch Set 1: Owners-Override+1\n"
                 + "\n"
-                + "By voting Owners-Override+1 the code-owners submit requirement is still overridden by <GERRIT_ACCOUNT_1>\n");
+                + "By voting Owners-Override+1 the code-owners submit requirement is still"
+                + " overridden by <GERRIT_ACCOUNT_1>\n");
 
     Ref metaRefAfterRewrite = repo.exactRef(RefNames.changeMetaRef(c.getId()));
     assertThat(metaRefAfterRewrite.getObjectId()).isNotEqualTo(metaRefBeforeRewrite.getObjectId());
@@ -1997,32 +2062,50 @@
     assertThat(commitHistoryDiff)
         .containsExactly(
             "@@ -8 +8 @@\n"
-                + "-By voting Code-Review+2 the following files are now code-owner approved by Change Owner:\n"
-                + "+By voting Code-Review+2 the following files are now code-owner approved by <GERRIT_ACCOUNT_1>:\n"
+                + "-By voting Code-Review+2 the following files are now code-owner approved by"
+                + " Change Owner:\n"
+                + "+By voting Code-Review+2 the following files are now code-owner approved by"
+                + " <GERRIT_ACCOUNT_1>:\n"
                 + "@@ -11,2 +11,2 @@\n"
-                + "-By voting Any-Label+2 the code-owners submit requirement is overridden by Change Owner\n"
-                + "-By voting Other-Label+2 the code-owners submit requirement is still overridden by Change Owner\n"
-                + "+By voting Any-Label+2 the code-owners submit requirement is overridden by <GERRIT_ACCOUNT_1>\n"
-                + "+By voting Other-Label+2 the code-owners submit requirement is still overridden by <GERRIT_ACCOUNT_1>\n",
+                + "-By voting Any-Label+2 the code-owners submit requirement is overridden by"
+                + " Change Owner\n"
+                + "-By voting Other-Label+2 the code-owners submit requirement is still overridden"
+                + " by Change Owner\n"
+                + "+By voting Any-Label+2 the code-owners submit requirement is overridden by"
+                + " <GERRIT_ACCOUNT_1>\n"
+                + "+By voting Other-Label+2 the code-owners submit requirement is still overridden"
+                + " by <GERRIT_ACCOUNT_1>\n",
             "@@ -8,3 +8,3 @@\n"
-                + "-By voting Any-Label+2 the code-owners submit requirement is overridden by Change Owner\n"
-                + "-By voting Other-Label+2 the code-owners submit requirement is still overridden by Change Owner\n"
-                + "-By voting Code-Review+2 the following files are now code-owner approved by Change Owner:\n"
-                + "+By voting Any-Label+2 the code-owners submit requirement is overridden by <GERRIT_ACCOUNT_1>\n"
-                + "+By voting Other-Label+2 the code-owners submit requirement is still overridden by <GERRIT_ACCOUNT_1>\n"
-                + "+By voting Code-Review+2 the following files are now code-owner approved by <GERRIT_ACCOUNT_1>:\n",
+                + "-By voting Any-Label+2 the code-owners submit requirement is overridden by"
+                + " Change Owner\n"
+                + "-By voting Other-Label+2 the code-owners submit requirement is still overridden"
+                + " by Change Owner\n"
+                + "-By voting Code-Review+2 the following files are now code-owner approved by"
+                + " Change Owner:\n"
+                + "+By voting Any-Label+2 the code-owners submit requirement is overridden by"
+                + " <GERRIT_ACCOUNT_1>\n"
+                + "+By voting Other-Label+2 the code-owners submit requirement is still overridden"
+                + " by <GERRIT_ACCOUNT_1>\n"
+                + "+By voting Code-Review+2 the following files are now code-owner approved by"
+                + " <GERRIT_ACCOUNT_1>:\n",
             "@@ -8 +8 @@\n"
-                + "-By removing the Code-Review+2 vote the following files are no longer explicitly code-owner approved by Other Account:\n"
-                + "+By removing the Code-Review+2 vote the following files are no longer explicitly code-owner approved by <GERRIT_ACCOUNT_2>:\n"
+                + "-By removing the Code-Review+2 vote the following files are no longer explicitly"
+                + " code-owner approved by Other Account:\n"
+                + "+By removing the Code-Review+2 vote the following files are no longer explicitly"
+                + " code-owner approved by <GERRIT_ACCOUNT_2>:\n"
                 + "@@ -12 +12 @@\n"
                 + "-The listed files are still implicitly approved by Other Account.\n"
                 + "+The listed files are still implicitly approved by <GERRIT_ACCOUNT_2>.\n",
             "@@ -10 +10 @@\n"
-                + "-By removing the Owners-Override+1 vote the code-owners submit requirement is no longer overridden by Change Owner\n"
-                + "+By removing the Owners-Override+1 vote the code-owners submit requirement is no longer overridden by <GERRIT_ACCOUNT_1>\n",
+                + "-By removing the Owners-Override+1 vote the code-owners submit requirement is no"
+                + " longer overridden by Change Owner\n"
+                + "+By removing the Owners-Override+1 vote the code-owners submit requirement is no"
+                + " longer overridden by <GERRIT_ACCOUNT_1>\n",
             "@@ -11 +11 @@\n"
-                + "-By voting Any-Label+2 the code-owners submit requirement is overridden by Change Owner\n"
-                + "+By voting Any-Label+2 the code-owners submit requirement is overridden by <GERRIT_ACCOUNT_1>\n");
+                + "-By voting Any-Label+2 the code-owners submit requirement is overridden by"
+                + " Change Owner\n"
+                + "+By voting Any-Label+2 the code-owners submit requirement is overridden by"
+                + " <GERRIT_ACCOUNT_1>\n");
     BackfillResult secondRunResult = rewriter.backfillProject(project, repo, options);
     assertThat(secondRunResult.fixedRefDiff.keySet()).isEmpty();
     assertThat(secondRunResult.refsFailedToFix).isEmpty();
@@ -2039,34 +2122,30 @@
             getChangeUpdateBody(c, "Assignee added", "Assignee: " + assigneeIdentToFix),
             getAuthorIdent(changeOwner.getAccount()));
 
-    ChangeUpdate changeAssigneeUpdate = newUpdate(c, changeOwner);
-    changeAssigneeUpdate.setAssignee(otherUserId);
-    changeAssigneeUpdate.commit();
-
-    ChangeUpdate removeAssigneeUpdate = newUpdate(c, changeOwner);
-    removeAssigneeUpdate.removeAssignee();
-    removeAssigneeUpdate.commit();
+    // Valid commits
+    writeUpdate(
+        RefNames.changeMetaRef(c.getId()),
+        getChangeUpdateBody(
+            c,
+            "Assignee added: <GERRIT_ACCOUNT_2>",
+            "Assignee: " + getValidIdentAsString(otherUser.getAccount())),
+        getAuthorIdent(changeOwner.getAccount()));
+    writeUpdate(
+        RefNames.changeMetaRef(c.getId()),
+        getChangeUpdateBody(c, "Assignee deleted: <GERRIT_ACCOUNT_2>", "Assignee:"),
+        getAuthorIdent(changeOwner.getAccount()));
 
     Ref metaRefBeforeRewrite = repo.exactRef(RefNames.changeMetaRef(c.getId()));
 
     ImmutableList<RevCommit> commitsBeforeRewrite = logMetaRef(repo, metaRefBeforeRewrite);
 
     int invalidCommitIndex = commitsBeforeRewrite.indexOf(invalidUpdateCommit);
-    ChangeNotes notesBeforeRewrite = newNotes(c);
 
     RunOptions options = new RunOptions();
     options.dryRun = false;
     BackfillResult result = rewriter.backfillProject(project, repo, options);
     assertThat(result.fixedRefDiff.keySet()).containsExactly(RefNames.changeMetaRef(c.getId()));
 
-    ChangeNotes notesAfterRewrite = newNotes(c);
-    assertThat(notesBeforeRewrite.getPastAssignees())
-        .containsExactly(changeOwner.getAccountId(), otherUser.getAccountId());
-    assertThat(notesBeforeRewrite.getChange().getAssignee()).isNull();
-    assertThat(notesAfterRewrite.getPastAssignees())
-        .containsExactly(changeOwner.getAccountId(), otherUser.getAccountId());
-    assertThat(notesAfterRewrite.getChange().getAssignee()).isNull();
-
     Ref metaRefAfterRewrite = repo.exactRef(RefNames.changeMetaRef(c.getId()));
     assertThat(metaRefAfterRewrite.getObjectId()).isNotEqualTo(metaRefBeforeRewrite.getObjectId());
 
@@ -2145,18 +2224,13 @@
     assertThat(result.fixedRefDiff.keySet()).containsExactly(RefNames.changeMetaRef(c.getId()));
 
     ChangeNotes notesAfterRewrite = newNotes(c);
-    assertThat(notesBeforeRewrite.getPastAssignees())
-        .containsExactly(changeOwner.getAccountId(), otherUser.getAccountId());
-    assertThat(notesBeforeRewrite.getChange().getAssignee()).isNull();
     assertThat(changeMessages(notesBeforeRewrite))
         .containsExactly(
             "Assignee added: Change Owner <change@owner.com>",
-            "Assignee changed from: Change Owner <change@owner.com> to: Other Account <other@account.com>",
+            "Assignee changed from: Change Owner <change@owner.com> to: Other Account"
+                + " <other@account.com>",
             "Assignee deleted: Other Account <other@account.com>");
 
-    assertThat(notesAfterRewrite.getPastAssignees())
-        .containsExactly(changeOwner.getAccountId(), otherUser.getAccountId());
-    assertThat(notesAfterRewrite.getChange().getAssignee()).isNull();
     assertThat(changeMessages(notesAfterRewrite))
         .containsExactly(
             "Assignee added: " + AccountTemplateUtil.getAccountTemplate(changeOwner.getAccountId()),
@@ -2181,7 +2255,8 @@
                 + "-Assignee added: Change Owner <change@owner.com>\n"
                 + "+Assignee added: <GERRIT_ACCOUNT_1>\n",
             "@@ -6 +6 @@\n"
-                + "-Assignee changed from: Change Owner <change@owner.com> to: Other Account <other@account.com>\n"
+                + "-Assignee changed from: Change Owner <change@owner.com> to: Other Account"
+                + " <other@account.com>\n"
                 + "+Assignee changed from: <GERRIT_ACCOUNT_1> to: <GERRIT_ACCOUNT_2>\n",
             "@@ -6 +6 @@\n"
                 + "-Assignee deleted: Other Account <other@account.com>\n"
@@ -2244,7 +2319,8 @@
                 + "-Assignee added: Change Owner\n"
                 + "+Assignee added: <GERRIT_ACCOUNT_1>\n",
             "@@ -6 +6 @@\n"
-                + "-Assignee changed from: Change Owner <change@owner.com> to: Other Account <other@account.com>\n"
+                + "-Assignee changed from: Change Owner <change@owner.com> to: Other Account"
+                + " <other@account.com>\n"
                 + "+Assignee changed from: <GERRIT_ACCOUNT_1> to: <GERRIT_ACCOUNT_2>\n",
             "@@ -6 +6 @@\n"
                 + "-Assignee deleted: Other Account\n"
@@ -2280,17 +2356,12 @@
     ImmutableList<RevCommit> commitsBeforeRewrite = logMetaRef(repo, metaRefBeforeRewrite);
 
     int invalidCommitIndex = commitsBeforeRewrite.indexOf(invalidUpdateCommit);
-    ChangeNotes notesBeforeRewrite = newNotes(c);
 
     RunOptions options = new RunOptions();
     options.dryRun = false;
     BackfillResult result = rewriter.backfillProject(project, repo, options);
     assertThat(result.fixedRefDiff.keySet()).containsExactly(RefNames.changeMetaRef(c.getId()));
 
-    ChangeNotes notesAfterRewrite = newNotes(c);
-    assertThat(notesBeforeRewrite.getChange().getAssignee()).isEqualTo(otherUserId);
-    assertThat(notesAfterRewrite.getChange().getAssignee()).isEqualTo(otherUserId);
-
     Ref metaRefAfterRewrite = repo.exactRef(RefNames.changeMetaRef(c.getId()));
     assertThat(metaRefAfterRewrite.getObjectId()).isNotEqualTo(metaRefBeforeRewrite.getObjectId());
 
diff --git a/proto/cache.proto b/proto/cache.proto
index 0cecdea..7063ee5 100644
--- a/proto/cache.proto
+++ b/proto/cache.proto
@@ -198,14 +198,7 @@
   string server_id = 20;
   bool has_server_id = 21;
 
-  message AssigneeStatusUpdateProto {
-    // Epoch millis.
-    int64 timestamp_millis = 1;
-    int32 updated_by = 2;
-    int32 current_assignee = 3;
-    bool has_current_assignee = 4;
-  }
-  repeated AssigneeStatusUpdateProto assignee_update = 22;
+  reserved 22;  // assignee_update;
 
   // An update to the attention set of the change. See class AttentionSetUpdate
   // for context.