I think 2, probably not 3, perhaps 4 ("the teleporters control the castle province but the army move").
(iirc I've tried to intercept one of your armies in 300mp some turns ago, taking a province between your starting position and your destination in magical phase, but your army managed to reach the destination anyway - but I may be wrong if you had another army I couldn't see with same kind of troops).
Heck, my guess would be 3. Try it and report back.
I'm playing Late Atlantis right now, and having fun playing with the possibilities achievable with flying, sailing, amphibious commanders...