That or we'll finally get a turret, since, you know, it has a turret.
But no rear firing arc.
Given that, during the battle scene on Maz's planet we quite clearly see a TIE/sf firing out its rear, I think a rear firing arc is more than likely actually.
Except if you try to fire that turret in a 360 degree, you shoot off your wing panels
http://starwars.wikia.com/wiki/TIE/sf_space_superiority_fighter.
