"Never trust a Chieftess with planes!".
Rebasing has a range-limit. You cannot send planes to a city on the other side of the world in 1 turn, you need 2 or maybe 3. I'm not sure an group-auto-rebase-key exists. I think Chieftess' suggestion works the easiest in reality.
Now if there was such a key for Group-Bombarding then it wouldn't get boring to bomb a SoD with 200+ stealth bombers for 6 consecutive turns. Auto-bombard doesn't work as the stack moves...