I've been doing the yo-yo method, even in '42. Dive when airplanes are visually spotted and keep a close eye on them when picked up on the air-search radar and dive only when they reach 5 nm range. I surface in about half an hour to an hour after diving.
I have been caught a couple of times and suffered some damage when an airplane has made an accurate drop, but nothing severe enough to cause an early end to a patrol.
I might stay down in the late afternoon-early evening until sunset to give my crew a "rest" before surfacing for the night.
The only time I might stay down all day is if I'm patrolling near a harbor or air patrols have been a really
big nuisance. I don't live rigidly by doctrine though, mine or the navy's. I try to adapt as the situation warrants.