Hello. I have tested the new firware. The stability is better, and now after losing the connection (just 1 time on 10 time) the device resume connection in 10-15 seconds.I enabled the develop build for your device. Don't think it will help, but you can try Please report back it it helped or not.
Sometimes happen one strange thing now, the phone lost all the BT pairing. Could be related to permission of the android auto app to manage the BT connection?