For those wondering about a safe protocol to taper prednisone, it's worth reading the “British Society for Rheumatology guideline on diagnosis and treatment of giant cell arteritis: executive summary.” You can find it here.
https://academic.oup.com/rheumatology/article/59/3/487/5714025
There's also a U.S. version of this guideline, but I prefer the UK version because it's more gradual. You'll want to look at tables 1, 2, and 3 for the tapering information.

My rheumatologist uses the U.S. version of this table, but I like the UK version better because it's slower.

Personally, if I can get down to 5mg of prednisone without symptoms, I will probably stay at that level. At 82, the mild symptoms of “Low Dose “ prednisone do not justify the risk of future flares. That’s just my personal approach.