Daily Maintenance run incorrectly

Hello everyone,

I have set up the Daily Maintenance as UTC + 8 :

And my user preferences:

However, when I used the system, it informed me that the Daily Maintenance started at 11 a.m. in my country:

When I checked the snapshot, the snapshot time showed:

I dont know why the daily maintenance ran at 11 a.m .

It should be run at 1 a.m like the setting.

Is there an Oracle bug?

Thanks!