FYI to everyone. Remember that when you register you are selecting a preference only. Nothing is set in stone, though the C.O.'s try very are to get everyone into what they want. You can request a transfer when you get access (after registering) to the Allied Tunisia forum.
Further, go ahead and register for a ride you might not want as much so as to fill all available slots. If this happens and there are more people wanting to play, the powers-that-be often increase the number of squadrons and rides to accomodate, so you may get your preferred ride that way. No guarantee, but it does happen.
And still further, if you show your face for another scenario after this one, and you didn't get the C.O. killed in battle or something like that, you'll know how scenarios play out and might get a better chance at your preferred ride next time. Actually, you'll probably know to register earlier by then.