Yeah I'm expecting XB2 to get a "please understand" delay to 2018. XCX was only released in 2015, and that took them about 5 years to make, I find it hard to believe they'd have a sequel ready in 2.
My theory is they had one group working on closing out X's development while another was making headway on 2's. Not sure if that will be enough for 2 to hit 2017, but could explain it being at a nice point in development. It's realy the only game I am worried about missing the year, everything else looks to hit it comfortably I think.