I decided to stop worrying about battery health. My XS is at 92% after 10 months, but my phone is working just fine. I can’t tell any difference in performance from when I first got it. Unless it drops below 80% or you notice significant performance decline, then don’t worry about battery health. Apple won’t do anything if it’s 80% or above. I used to check it regularly but decided to quit looking at. If your phone works fine, who cares what the battery health is. Also, from what I have read it’s not completely accurate anyway.