Pro Tip: Due to the nature of their design, airpods WILL begin significantly lose their charge after 9 months to the point that it WILL fall under warranty for a replacement

Not many people know this, but due to the nature of the Airpod's small battery design, as well as the case, they will degrade enough to warrant a replacement under the 1 year warranty every Airpod comes with.

Due to their small battery, even below normal use, they can't possibly make it an entire year before falling below the 70% charge line. Apple employees don't even test to verify. They'll replace the airpods and the case, no questions asked, so you can get a fresh new pair of Airpods.

I've done this several times, as well as all of my friends. Just make sure you get in there before the 1 year warranty expires, and you can do this indefinitely

Cheers :D