Appears to have been NOT the computer, but instead a home wifi router programmed to be a "universal repeater" had reverted back to nothingness...and therefore whenever the RMS connected to THAT ssid....it lost internet access. The errant router was discovered yesterday and properly configured to provide better WIFI for that end of the residence. That explained several little oddities that were discovered.
I regret that I had to "upgrade" the NND4FL computer from the trusty VISTA machine that operated flawlessly year after year. The Window 10 machine is still dropping off the home network every few nights.....and I don't know why. I have it rebooting twice daily to try and keep it on the network. It is only a few feet from a wifi bridge to be sure it has good signal....and still not working to my satisfaction. Next I may try a ethernet cable (hard-wired). Perhaps this will eventually get fixed.