DOCSP-45442 (#621) (#630)

Author: sonderdonk-mdb

source/reference/cutover-process.txt

@@ -75,6 +75,8 @@ Steps
 
    .. step:: Stop any write operations to the synced collections on the source.
 
+      - Wait for all transactions on the source cluster to either commit or 
+        abort.
       - If you start ``mongosync`` with ``enableUserWriteBlocking``
         set to ``true``, ``mongosync`` blocks all write operations on
         the entire source cluster during the commit (step 4) for you.