White stormed out of his end of season meeting and messaged on social media that he was gone. (That's how it was taken by everyone.) The end of season meeting is about on the field stuff it isn't where you discuss a contract. It's pretty obvious to me they had decided at that point that he had not been good enough, will not get better, and it was best for the team to move on.
But unless he or the team ever talks about it, we will never know for sure. Personally, as I said long ago, I am fine with it as he was really part of the issues our defense had. He just wasn't as good last season as he was the year before. That's what I saw.