diff --git a/.github/workflows/meeting-reminder.yaml b/.github/workflows/meeting-reminder.yaml
index 0fb77ca..a928c80 100644
--- a/.github/workflows/meeting-reminder.yaml
+++ b/.github/workflows/meeting-reminder.yaml
@@ -1,6 +1,8 @@
 name: Send out reminder about monthly meeting
 
 on:
+  # Be careful when changing the schedule:
+  # CRON uses _or_ when day-of-month and day-of-week are provided.
   schedule:
     - cron: '1 0 * * THU'
   workflow_dispatch: