Optional Rule 10.2 is in the non-combat section.
During non-combat, you land the aircraft that took part in combat (10.3) and can move aircraft that did not (10.1), so both options would be available.
Does one have to declare where the fort will be placed at the beginning of construction? Same question for bases.
@sjelso Yes, see page 26 under Facilities.
That way, all facilites under constuction are subject to strategic bombing or capture.
There is also an optional rule (15.8) to declare multi-stage ships under construction. It’s more realistic that way.