Fantastic Four pushed back to late Summer

In addition to Fox announcing a Deadpool film, they made a couple more changes to their schedule. The upcoming Fantastic Four reboot has been pushed back from June 16, 2016 to August 17, 2015. It is taking the spot of Assassin's Creed which seems to have been pulled from the schedule altogether.

Many are speculating that Fox is going to test the August market after Marvel's overwhelming success with Guardians of the Galaxy. For a film that has yet to have any official marketing (seriously, not even a logo), it is somewhat curious as to what caused a delay. Is it to try and have a better box office market or is it because they needed more time? Fantastic Four stars Miles Teller, Michael B. Jordan, Jamie Bell, Kate Mara, and Toby Kebbell.
As far as Assassin's Creed goes, this is even more curious. Michael Fassbender has been attached to star and produce for quite sometime, but Fox removing it from the schedule entirely isn't a good sign. Production on this has been moving at turtle speed and with it still not moving forward when it had a release date of less than a year away was a bit odd. The project isn't officially dead at this point, but it has a big fat "TBD" as of right now.