Sorry to hear you'll be going through the radiation treatments over the holidays.
Sometimes the slow moving aspect of PCa gives us a bit of a window to take our time.
I agree that in your current situation, you don't have the luxury of that window of time.
With your PSA, I don't think waiting until after the holidays is an option.
Hopefully your second radiologist will concur with your first and you'll have a solid plan in place.
Good luck!
Dave