[deleted] Yeah, I think I spoke too soon. Searching around online, it seems like ending up with duplicated devices (the same device listed twice, as if it's too different ones in one's Google account or in Play Store) is a thing that happens pretty often. Doing a factory reset seems to be one of the things that causes this. So it's not specific to Graphene or Seedvault. It's annoying though and there seems to be no solution. You can log out of the fictive device, but it will still show up in Play Store.