Where can you find the housekeeping tasks in SnapCenter version 5 & 6 (on Windows). Several KB articles refers to Windows Tasks Scheduler, but that seems to a long time ago.
You can also create a schedule using powershell and the syntax presented in the KB article but there is no apparent way to verify that the schedule is actually there, or if you have multiple entries of the same housekeeping task.
Example of a housekeeping task: SnapCenter_RemoveSecondaryBackup