Or you can just root for the teams you like best, and against the ones you do not. Or for gamblers, you can root for the teams you bet on.
Changing who you root for, on a weekly basis, based on your hunch on what team might be the biggest threat to the Bills making the playoffs, is pretty absurd, IMO. Maybe for the final game, or two, of the season, I can understand, But now? It's too early to know who will be the biggest impediment to the Bills, at this stage, for many matchups.