I feel like glow never changes the ovulation or period expected dates even though I’ve literally given it years of data. My period is irregular so I just accepted that as the reality of tracking with an irregular period. To my surprise though, I decided to enter all my data into my iPhone health app and I do have an iwatch but not the new fancy one with BBT tracking, and amazingly I’m getting much more accurate predictions. I’m not sure if it accounts for any of my iwatch data which I get glow doesn’t have but I did just want to share if you aren’t getting accurate predictions, maybe try out apple. There aren’t as many metrics you can track, but in the end, I just care about accurate period and ovulation predictions.