It's good to hear an update from you. Although this silly little group of forum members is the last thing you should care about, we've all been concerned for you and your family. I'll be rooting for Mrs. IRBS to keep improving, so you 2 can get back home.
I noticed the same with Google navigation while we were in Europe. Except for the day that Mrs. Scotch's phone was heading to Zurich (without us), I kept my phone in Airplane mode. But as long as I pulled-up the map from the hotel via Wi-Fi, all of that info about streets, restaurants, and landmarks would continue to display on the map, while the GPS tracked where we were.I have been taking advantage of Apple Maps navigating around Scranton. I discovered that as long as you have WiFi/data when you enter the route, you don't need to be under data to be navigated. Nice feature.