diff --git a/zuul/scheduler.py b/zuul/scheduler.py
index 6a6c5d1..8f909eb 100644
--- a/zuul/scheduler.py
+++ b/zuul/scheduler.py
@@ -563,7 +563,7 @@
             return
 
         # Preprocessing for ref-update events
-        if hasattr(event, 'refspec'):
+        if event.ref:
             # Make sure the local git repo is up-to-date with the remote one.
             # We better have the new ref before enqueuing the changes.
             # This is done before enqueuing the changes to avoid calling an