Hopefully not too long. I think one more losing season would have done Polk in had he stayed. I say that because attendance was plummeting, interest was waning, and Polk was starting to lose some of his most loyal people. Even though he is a legend, people will only put up with so much.
I do think that part of the reason that Polk retired when he did was because he saw that this team just didn't have it and he wasn't going to be able to do anything about it. There would have been a ton of pressure on Polk to fire McNickle and for him and the team to perform next year had he stayed. He also would be without his safety net LT to try to stave people off. Also, Polk knows that the last coach that had a losing season at State was bought out by the Cigar Boys. He may have had a similar fate, as I doubt the Cigar Boys give a rip about what his croonies think.
I think his plan was to try force Raffo in and hope that Byrne would go for it with the school President and AD position up in the air. Polk was probably going to use Raffo to keep him "inside" the program. I don't believe even Polk really thinks that Raffo is the best choice for the job. It's all a charade.