@rnm, You sound like you are doing well with your tapering off of prednisone. You do ask a really good question but I'm not sure there is an answer that is the same for everyone since it can be different for each of us with PMR. You mention that you still have some pain almost a year into your PMR diagnosis and starting prednisone. My first time with PMR lasted 3 and 1/2 years and the last six months was going back and forth between 1 mg and 1/2 mg before I could finally stop taking it. My second occurrence with PMR six years later and only lasted 1 and half years before I was able to stop taking the prednisone. I kept a daily log of my dose and pain level and my acceptable level of pain when I first got up in the morning was 2 or less on a scale of 0 to 10. I never used Tylenol or other OTC other than for headaches. My 2 or less level of pain generally got better after I got up in the morning and started my daily routine.

Here's some information that talks about it.
"While the aim is to stop prednisone use as soon as possible, the average duration of prednisone use is one to two years."
-- Polymyalgia rheumatica (PMR) – look before you leap: https://bpac.org.nz/2023/pmr.aspx

If you have time, @dadcue shared a great video that provides some understanding of the tapering issue.
-- Video: Steroids and PMR - International Panel of Doctors
https://connect.mayoclinic.org/discussion/video-steroids-and-pmr-international-panel-of-doctors/
Just curious, how would you rate the pain you describe as the pain you have been treating with Tylenol?