I have not written to Support. Since my original post (including all of those dropoffs) I’d say it’s dropped off seven or eight times. Of those, five have been just after 12am. Although I no longer think it’s a network congestion probem, I do have a new router on order due in about a week. The disconnects seem to happen in waves. I think I went six days without problems, then I had disconnects on Friday, Saturday, and Sunday. It did not disconnect this morning.
The strangest things about my issue are the relatively consistent disconnect time, and the lack of backfilling even for a 15 minute period (on Sunday).