There's several buttons in the circuit. If you figure out what those do, the laws of time of this circuit's universe are yours to behold.

Note to future me to fix the following bug (if it even exists in the real world due to propagation delay). 

The set 1 function of #2 works in the sub-circuit but fails to work for the output pulse in the main circuit. This is troubling to say the least. So I've decided to change hour 12:00 to 00:00.