Wait until they fix a big problem of stats first, you’ll lose all you amp stats if you update, that happened to many, so, I suggest waiting until the release a new version newer than 6.2
I also noticed the same thing and thought it was related to Google update until I tested a few amp pages myself. I can confirm that the Jetpack plugin is not counting AMP pages anymore. This is a big issue. So, we wait for a solution.
