According to WitP manual at page 132:
7.2.2.10 Impact of Altitude Selection
Planes on a Sweep Mission will always drop to 100 feet and strafe (taking flak at their set altitude and again at 100 feet).
So... this implies that user can set the fighters (or fighter-bombers) for "Sweep" mission at 10000 ft and they would still drop to 100 ft to strafe after air-to-air combat is done...
But I can't recall ever seeing my fighters (or fighter-bombers) that were doing "Sweep" mission at whatever altitude except 100 ft to strafe.
Can someone please confirm this?
Leo "Apollo11"