I have a MBP 14" M1. I had the $99/year AC+ option. A week or so before the year ended, I thought I might cancel it and just take my chances, since I am pretty careful with my stuff. After I cancelled the auto-renew option — but still before the coverage had ended — my wife prevailed upon me to renew the policy. I did so by going back to the site and selecting Auto-Renew, and the webpage confirmed it. Cool! All done! Well, yes and no.
About two weeks after "auto-renewing" the policy, I noticed on Apple's My Devices page that my MBP was not under warranty. I called Apple Support, spoke with Rep who said I could renew within 30 days after it expires. Cool! Well, not really.
After being put on hold and forwarded to another Rep, I was informed that once the coverage is cancelled, it cannot be renewed — even though I chose to Auto-Renew before warranty expired.
Lesson? Be very careful about doing what you think you might want to do. Choose wisely, Grasshoppers!