You can have a shift over midnight.
You will have to use an alternate datebook
datebk5 is one and there are a few others.
They have a few other bells and whistles as well but do cost.
Not sure if they implement refinement to the minute (I doubt it)
I just add a note to the item and use a shortcut to boilerplate text
A/C
Day
Ngt
On
Off
Apps
and then fill in the details.
You can get real smart and extract this data from the desktop if you wish.
Aside from that they are a great toy ...whoops I meant tool
MAx