I’m surprised because being an NFL head coach is the high point all the various assistant coaches, offensive coordinators,etc. Would eventually aspire to. I don’t know the details of the Bills coach and team situation. But seems odd that a coach would walk away from being an NFL head coach.
It appears he will get a bunch of offers (likely in a better geographic locale and higher salary - and just getting out of NYS for the same salary probably gives him a big raise via lower taxes).
He also has a special contract clause that pays him his full 2015 salary from Buff even if he is working at another HC job in the NFL - that’s more lucrative than the typical NFL contract deal.