Delete Events Older Than N Days

Currently on BO 4.1SP3.

Through the CMC, I've just changed the ADS configuration settings in the Auditing Dashboard to delete events older than a specific number of days (previously, this was set to a higher number).

My question comes down to: When does the cleanup actually begin where it will start to delete the old events?

And is there a way to kick off the process at a specific time?

Thanks