Update... For the last three nights, overnight, I streamed content (YouTube TV) rather than an OTA antenna signal. I had no network connectivity loss or problems doing this. Now I don't always have a internet connection loss from OTA -- but generally, at least one night in three, I would expect to have the issue.
So, what does this mean? It seems I don't have an issue maintaining an active network connection/stream. Why the issue when watching OTA overnight? Perhaps, when the TV is on but the network connection is idle for some time, a network connection request (background check for updates, maybe) fails and the internet connection becomes FUBAR.
This I know--looking at the TV first thing in the morning: If the bottom-bezel LED light is double-blinking, internet connection isn't working regardless what's its status says. If the LED light is not blinking, internet connectivity should be good.
Any other thoughts?