He's just 2yrs older than Henne. (K, 3 come late November) If he continues to play around this level, I say the wise move is to improve the defense, draft playmakers and get a good developmental QB with a good chance to start eventually, like Ponder, who also fits Chan's offense to a T, in the 3rd or 4th round. None of the top three QB's in this class will be ready to start for an nfl squad next season and maby even the next.
Because rationally, the Bills could win now with Fitz as the starter with more talent to throw to, and a defense with a pulse. A young QB, even a football genius such as Luck, would take 2yrs or so to get to the competency level Fitz is at right now in Gailey's offense, and by that time Chan would be gone.