Sync only in timeslot (for productivity)

Its an question or an idea. Not sure. Don’t know if its possible right now.

I want EM client only syncing in specific time slots. For example 12:30 and 17:30. is this possible?

I tried the settings but the max delay in syncing is 99 minutes.

Its is a productivity idea of Tim Ferries from the 4 hour work week btw.

Hope its possible.