Add maintainence mode start date

Rishit-dagli · web-flow · commit e2257a8aef6d · 2023-08-12T18:54:42.000-04:00
diff --git a/data/releases/schedule.yaml b/data/releases/schedule.yaml
@@ -7,6 +7,7 @@ schedules:
   next:
    release: 1.28.1
   cherryPickDeadline: 2023-09-08
+  maintenanceModeStartDate: 2023-08-28
   targetDate: 2023-09-13
   endOfLifeDate: 2024-10-28
   previousPatches:
