diff --git a/go/logic/migrator.go b/go/logic/migrator.go
index aa9a97c1c..612fe056c 100644
--- a/go/logic/migrator.go
+++ b/go/logic/migrator.go
@@ -111,7 +111,15 @@ func NewMigrator(context *base.MigrationContext, appVersion string) *Migrator {
 		ghostTableMigrated:         make(chan bool),
 		firstThrottlingCollected:   make(chan bool, 3),
 		rowCopyComplete:            make(chan error),
-		allEventsUpToLockProcessed: make(chan *lockProcessedStruct),
+		// Buffered to MaxRetries() to prevent a deadlock when waitForEventsUpToLock times
+		// out. The sentinel applyEventFunc may still be queued in applyEventsQueue when the
+		// timeout fires; when the worker eventually executes it, it sends on this channel
+		// with no active receiver. An unbuffered channel would block the worker permanently:
+		// the queue fills, the listener goroutine stalls, heartbeat lag grows unboundedly,
+		// and no further cutover attempts are made. With a buffer sized to the retry limit
+		// the send always completes immediately. Stale sentinels accumulate in the buffer
+		// and are discarded by the stale-skip loop in waitForEventsUpToLock.
+		allEventsUpToLockProcessed: make(chan *lockProcessedStruct, context.MaxRetries()),
 
 		copyRowsQueue:     make(chan tableWriteFunc),
 		applyEventsQueue:  make(chan *applyEventStruct, base.MaxEventsBatchSize),