When can I stop RTC server safely?(w/default scheduled task)

Hi, I recently chanded my RTC server's offline backup time from 3:00 to 23:59.

Then, I found that
- Data Warehouse Snapshot update task had not worked.
- Also, LDAPNightlySyncTask had not worked.

My understanding is:
- Data Warehouse Snapshot update runs every 0:00 (daily)
- LDAPNightlySyncTask runs every 1:00 (daily)

I think I should run offline backup another time.

My question is:

1) When can I stop & take offline backup safely (without stopping any task) by default setting?

2) Is there other task to be concidered ?

- Data Warehouse Snapshot
- LDAPNightlySyncTask
... something else?

3) Is there any guide/document about those scheduled task running on RTC server?

- What kind / How many Tasks
- When those Tasks work
- How to change default schedule
and so on.