Preliminary NTSB reports are usually pretty much it; rarely do they get changed.
So it came down to a stupid flight plan; stupid air boss and a pilot who forgot a primary rule: always know where all aircraft near you are.
I can bet the FAA pretty much will shut down any maneuvers and maybe even any flight formations from now on.
Any more disasters like this and I can see a virtual ban on anything but single aircraft flying over the airport.
Terrible tragedy that was completely preventable. Incompetence and overconfidence combined usually results in bad things.