"Malta" doesn't have a broad enough scope to be a full addon in and of itself. It requires a significant investment in Ship models and CV operations, and in the end, its VERY narrowly focused. Its certainly something to MOD when the plane sets becomes available..but who is going to play "Malta" over and over and over?
Keeping in mind that the coders are RUSSIAN
and that the original CORE of the IL2 series started with the Russian campaign, I think its logical in both time line and progress of the plane set. You get to integrate a lot of knew AC types that they already have in the bag, and grow the plan set.
I'll place my money on Barbarossa