Tasks fired after changing crontab schedule

[yamac-kurtulus]

Summary:

I am trying to understand why the tasks are fired immediately after rescheduling by changing the schedule. I have encountered this problem with cron schedule but there is a chance that it would happen with others.

I had a task that's been going on everyday at 13:30 for a long time, I had to change the time to 16:00 PM today before the task triggers (around 12:20pm) When I save the task, it immediately fired, despite the new schedule is after 13:30. Why did this happen? What is the correct way to make such changes? Is this a bug or a feature?

• Celery Version: 5.3.1
• Celery-Beat Version: 2.5.0

Exact steps to reproduce the issue:

1. Create a scheduled task with cron, let it trigger once
2. Change the crontab to schedule the task to a later time
3. When you save it, the task triggers immediately although the schedule changed to a later time.

[hottwaj]

Similarly, We have recently had two separate occurrences of django-celery-beat sending tasks that were not due when it was restarted. This is a major issue and we'll likely have to sw

[mark-at-kluster]

see #537