Another thing that can be done by placing this after The Last Stand is give us a big time frame with which to work for reshaping Deadpool. I don't even particualarly like the character but know many do. So for those who'd like a better Deadpool this gap allows for that. Not that he's going to appear in TW but just tossing that as another benefit for moving past TLS.
So it seems TW is not going to ignore TLS.