if he is offered a guarantee to start and the money's ok - I imagine he'll bolt. And he should. He's young, but you only have so many years and he was the guy, so I would imagine he wants to be the guy again asap.
Of course this all depends on what kind of tape he puts down in the next 2 weeks. If it's really good, he may get an offer, if it's somewhere in between or good and bad, his price goes down and the offers might be more of the 'come on in and compete' type of deal.
If he doesn't get offered a starter salary / position, I don't see why he wouldn't come back here on a one year deal.
And can we please stop making stuff up about what the Rams should tell Stafford, or Stafford should tell the Rams about a timeline for retirement? Players make those decisions on their own with their families (or in the case of Brady, without).