I had navigation via Android Auto running a few days ago, just to make sure it was working with the latest Android version, and I was surprised to see that whenever I drove through an area in which I lost cellular signal, the screen blanked momentarily and then showed a message to the effect that it had switched over to the Honda Navigation service, and then resumed with the Honda Nav displayed. When I again had a cellular signal, it displayed a reverse message and back to Google Maps Navigation. That happened several times as I drove through a remote area. I was driving, so I couldn't copy down the exact language, but that's what I though was happening. I had no expectation that it could do that, and I don't recall anyone commenting on it before. I have a strong preference for Google Nav, for a variety of reasons, but the capability for it to spontaneously switch over to the Honda Nav system in the middle of an active navigation session, when cellular signal is lost could be hugely helpful when driving through extended areas without cellular.