diff --git a/src/main/resources/static/automerger.js b/src/main/resources/static/automerger.js
index f6a3b5b..d8995d5 100644
--- a/src/main/resources/static/automerger.js
+++ b/src/main/resources/static/automerger.js
@@ -71,7 +71,7 @@
     }
 
     function getDownstreamConfigMap() {
-        var changeId = currentChange.id;
+        var changeId = currentChange._number;
         var revisionId = currentChange.current_revision;
         var url = `/changes/${changeId}/revisions/${revisionId}` +
                    `/automerger~config-downstream`;