Maybe... I noticed late last week (Wed, Thurs, or Fri) that when I told my google home to turn the temperature down it couldn't find the device or something. Just figured it was a fluke. Then Friday is when I saw all this, revoked SEI access and then saw my stuff (anything nest related and google home groups) was deleted. Maybe revoking SEI access deleted it? Maybe SEI access just went in and deleted it? Just hope to have something from Tivo or google ASAP on thisI would bet that this mass Home Deletion happened when Nest Accounts were upgraded to the new plan that they just rolled out.
So, like around July 10? I have no proof, but boy, mine were fine before that date.
Now, everything in my main "Home" is not in a home, but they're still linked to me, at least.