Thank you for the quick answer. :)
You might want to consider adding this issue to the Revised FAQ/Errata (just using the wording on the AA50 manual would do it). This issue turns up every once in a while on forums.
I in invade Western Europe with England and bring an AA-gun. Next turn Germany retakes Western Europe. What about the aa-gun. Is he allowed to move the aa-gun back to Germany og southern Europe in the same turn he invaded Western Europe?
You cannot move an AA gun you captured on the same turn.
The logic being:
The AA Gun was technically involved in a Combat (even if it did not fire at planes during the combat), so it cannot make a Non-combat move. The only pieces that defy this general rule are planes (explicitly excepted in the rulebook) and Panzerblitzing German tanks (German National Advantage - also explicitly excepted.)
This might also be explained as a common behaviour of the grey pieces - AA Guns and Complexes - in that if they are captured or liberated, the new owner doesn’t assume functional control of them until the end of the turn during which their capture or liberation occurred. I actually like this justification better than the one above.
~Josh
The above posters are correct, the AA cannot be moved in the same turn it is captured.
Another “rule rationalization” reason for it:
No land units are permitted to retreat from a combat zone after the battle is over.