Waste Water too
Mid-Atlantic Air Museum
Can air bombardment of passing fleets by the non-phasing player, during either the movement or combat phase, be intercepted by the phasing player's air units?
No, only DAS may be intercepted.
Also, is it possible to counter-air air units that bomb passing fleets during the movement phase?
No, counter air missions only take place during step 8c.
Finally, when is fleet bombardment against fleets changing bases resolved?
If you mean when is air interception against moving fleets resolved, it is resolved after any fleet combat by intercepting fleets opposing the move. It is implied that fleet movement can create a naval combat and then offensive naval missions create a second round of naval combat. So you should:
Declare moving fleets.
Defender announces interception and air attacks.
Attacker announces counter-interception and so on until no more interceptions.
Then resolve the combat in reverse order.
Finish with the air attack on the moving fleet.