It seems that Foreman sometimes forgets to apply the timezone logic (or it shows the info in GMT without clearly indicating it).
Example: I have a daily sync plan, and in the details of the plan it is marked:

Start Date: Jul 25, 2019 2:59:00 AM
Next Sync: August 22, 2019, 12:59 AM
Recurring logic: 3

(also the Sync Plan overview mentions this 12:59 AM).
However, when checking the "recurring logic" it says:
Last occurrence 2019-08-21 02:59:09 +0200
Next occurrence 2019-08-22 02:59:00 +0200

And the logs also correctly show that the sync always starts at 02:59:09 +0200
My browser should have the correct timezone, and my account profile indicated to use the browser timezone.

Also, the sync status shows in its overview that the sync of a repo started e.g. "about 7 hours ago". While this seems informative, it is not (I think the daytime info would be more useful).