I was diagnosed with PMR back in Jan. 2022 and put on 20mg Prednisone immediately and the pain also subsided immediately (like overnight). I had been completely debilitated for the previous 5 months. Basically could do nothing, even sit on toilet or reach around. Lost use of my right hand and had to where a splint, which effect my work. Couldn't dress very well. It took an extremely long time. Could not drive as my neck was not co-operating, or my arms and shoulders. It was a terrible time.
Pred was like the miracle cure, however, reducing the dosage is not easy. I'm down to 11.5 mg as of this week. Some pain, but mostly manageable. Not in a rush as small amounts at a time (like .5 mg) seem to work better than a huge drop. It's not a race to get off the Prednisone. It's about pain management and quality of life during this time. Don't get dragged into the "you must reduce quickly" thing that some doctors and rheumatologist tend to believe. My new GP says slowly and if the pain returns go up a bit and he says "at least you are trying". All the best!