Bomber Flying Techniques/Tactics (Dornier 217)

Hi,

I hope someone can help me with this one. I am interested in the behaviour/flying tactics of a Dornier 217 and have 2 questions: Once a bomber has dropped it's bombs would it return to base at a high altitude (presumably to avoid intruder patrols and flak)? In addition, is it feasible that on approach to base (within 25km) the aircraft would fly back and forth (east to west then turning 180 Degree)waiting for it's signal to land?

The reason I ask is that I am trying to explain the behaviour of an aircraft (I think it was a Do217) seen by my grandfather in his Beaufighter.

Thanks for all your help!