diff --git a/app/config.py b/app/config.py
index 37b0f4619..063ebc7e9 100644
--- a/app/config.py
+++ b/app/config.py
@@ -307,7 +307,7 @@ class Config(object):
             },
             'raise-alert-if-letter-notifications-still-sending': {
                 'task': 'raise-alert-if-letter-notifications-still-sending',
-                'schedule': crontab(hour=15, minute=30),
+                'schedule': crontab(hour=17, minute=00),
                 'options': {'queue': QueueNames.PERIODIC}
             },
             # The collate-letter-pdf does assume it is called in an hour that BST does not make a