Add more clarification of submodule subscription limitation
Change-Id: I68dea8f95127ea1fd7be2652b1b037d07788dca7
diff --git a/Documentation/user-submodules.txt b/Documentation/user-submodules.txt
index 0de3298..2754b45 100644
--- a/Documentation/user-submodules.txt
+++ b/Documentation/user-submodules.txt
@@ -204,9 +204,13 @@
adding submodule subscriptions.
When converting an existing submodule to use subscription by adding
-a `branch` field into the .gitmodules file, Gerrit does not make any
-change to the submodule's current revision until subsequent updates
-occur on the submodule.
+a `branch` field into the .gitmodules file, Gerrit does not change
+the revision of the submodule (i.e. update the superproject's gitlink)
+until the next time the branch of the submodule advances. In other words,
+if the currently used revision of the submodule is not the branch's head,
+adding a subscription will not cause an immediate update to the head. In
+this case the revision must be manually updated at the same time as adding
+the subscription.
=== Relative submodules
