I just did an extensive piece about the Jets QB options in 2013. What I found was, no matter what avenue the Jets take, keeping Sanchez as the starter just makes more logical sense.
The only hope for Sanchez to not be the Jets starter is for either a) he plays badly enough over the next month to start one of the backups or b) Mike Tannenbaum is fired. Even if Mr. T is fired, it still makes more fiscal sense for the Jets to keep no. 6.