Yesterday coming out of the underground parking garage at work, I noticed the LTE connectivity hadn't returned. I waited a few more minutes, and then tried a few reboots using the scroll wheels. No luck. I let the car sit for a few hours and then tried again with no improvement, so gave tech support a call. Since I had no connectivity (and no wifi to connect to) to help with their diagnosis, all they could do was book me an appointment at the service center. Fortunately, they had an opening first thing in the morning. Strangely enough, I also lost bluetooth connectivity at the same time the LTE went out, but that was fixed with a reboot of my iPhone. Service was ready to give me a loaner while they diagnosed the issue, but wanted to try a quick fix of power cycling the vehicle by disconnecting the 12V and reconnecting after a few minutes. That seemed to fix it (also got a FW update while they were at it). They said it sometimes happens with the modem, but to keep an eye on it in case I lost connectivity again. While it's annoying when technology starts to act up, I thought it would be helpful to document this as a troubleshooting step in case an appt with service is a ways away. I didn't realize how much I was relying on that connection until I lost it and saw traffic info, destination searching, music streaming, calendar appointments, remote status, etc. all inaccessible.