Due to recent developments with GSP's manager, Firas Zahabi, I feel if GSP beats Johny Hendricks he will fight Anderson Silva and retire win or lose. This will pave the way for Rory to get the Championship considering they have refused to fight each other.
Rory is set to fight Jake Ellenberger at UFC on Fox 8. If he gets through Jake I believe he is one fight away from a title shot with another top contender, probably Damian Maia if he's still winning. Then GSP will fight Anderson Silva and then retire. Rory will then fight someone else for the title.
Now keep in mind this is all only if Rory and GSP keep winning. If GSP loses and Rory wins against Ellenberger, then he should face Hendricks for the title. This is just my personal opinion on how I believe things will transpire. Please let me know your opinion!