My Opinion, you have reached the taper point. The kevzara has reduced the PMR inflamation but now that your getting lower on the prednisone your cortisol levels are not caught up. This increases the pain which increases inflammation. Its a vicious cycle created by the prednisone not the PMR. It will act like a flare but you will never get off prednisone by going back up. You need to taper more slowly or suffer through a couple weeks or even month to have your cortisol restart.