They used to do that, and stopped because if a power outage occurred
the clock would get off and the unit would appear to be broken as it
shut down in the daytime. With todays technology (wireless atomic
clocks for one, bios clocks with battery backup for another) there is
no reason not to bring it back. My Monogram is now on a 6 hr timer, ti
used to be 10 hr but that just didn't get it, so I upgraded(?) it.