I noticed this notification when I last used Android Auto. I'm obviously not updating until Graphene pushes a sanctified version of AA in the Graphene App Store.
Okay, good to know. I have a USB dongle that converts my car to Wireless AA. There are options to upgrade its firmware, and I've been avoiding it, because it works perfectly fine. My car also has no internet connection, so there's no way I could upgrade it without taking it to a dealer (not happening).