Congratulations on finding a dose of prednisone that works although 35 mg is a bit on the high side for PMR only. I settled on 35 mg when I was first diagnosed with PMR. Enjoy the higher dose while you can.

Other things were added to the mix when I stayed on that dose "long term". I had energy to spare until I started complaining about being short of breath with minimal exertion. My primary care doctor called it "exercise intolerance". He recommended an exercise tolerance test (ETT)
https://www.verywellhealth.com/exercise-tolerance-test-5213589
The ETT was interpreted as "normal" but I knew my exercise tolerance wasn't normal for me. My primary care doctor offered to do a pulmonary function test (PFT) but I declined that test.

My next visit to my doctor wasn't under ideal circumstances. I was on a long distance bicycle ride when I hit the proverbial wall. This had never happened before. It was also strange that I had an irregular pulse. When I told the story to my doctor, he thought I needed an EKG. He verified the slightly irregular pulse. The EKG result was more concerning because it revealed left ventricular hypertrophy (LVH).
https://www.mayoclinic.org/diseases-conditions/left-ventricular-hypertrophy/symptoms-causes/syc-20374314
I was told this condition was caused by high blood pressure except my blood pressure was never high and I had no history of any cardiac problems.

My doctor instructed me to take my blood pressure more often since I was taking a higher dose of prednisone. It didn't take me long to catch a blood pressure in excess of 200/100 but no other symptoms. I wound up in the emergency room. Three blood pressure medications were initiated. That was just the start of an extensive cardiovascular history that happened later.

Reducing your dose by 2.5 mg every 2 weeks might be too optimistic considering I was on higher doses for 12 years for PMR. I wish you good luck with your reduction plan. It usually takes people a couple of years to taper off prednisone when they have PMR.