Well, BFC have said a while back that the third game would be North Africa/Italy/Greece(?), and that the fourth game would be early western front, i.e. 1939/40. I would imagine anything more modern would have to be after that.
I hope they at least do Italy & North Africa before leaving WW2 behind. France/Low Countries/Norway would be OK I suppose, but doesn't interest me nearly as much. Looking forward to Tobruk, El Alamein, Anzio, Monte Cassino, etc...