I'm not surprised that they decided to split them into two separate releases; I was pretty much half expecting it to happen. Though I am surprised the final part is coming so soon after Q. Also, I'm not sure if the official title will be "?"... I always imagined that they were going to reveal the official title closer to the release date, so in this case, probably when Q is released.
As for them stretching out little content over two films, I have a feeling they will be veering off quite a bit from the original material from here, so anything can happen. Plus, judging from this
, it seems likely that more new characters will be introduced.
Also, anyone find it interesting that they will seemingly be going with a blue theme for Q? I just found it a bit surprising after the red and orange for the first two films... Though perhaps it shouldn't be surprising given that they went with Q instead of 急 for the title.