I'm hoping he can change his manuever dial to anything before he moves, but loses his attack for the round. I don't think the wording allows for it but I think it would be fun.
I really hope not, since that would be a waste of a PS 8 pilot. Changing your maneuver is only valuable if it sets up a better attack, if all you want to do is get out of trouble it's hard to beat a 5-straight and if you want to block then you aren't using a 40+ point E-wing.