I am sorry to have to say @ron_ferris that after firmware 4.22 SOtM have had problems with things like this. My Ultra have done this a couple of times and a re-burn of the SD card is the only thing that helps. It is not that difficult to re-burn the SD card perhaps you know someone that can help you?
I have been in contact with May at SOtM and right now I am trying out settings to se if it happens again and can send them feedback.
After it happened twice a couple of weeks ago I got a new SanDisk Ultra 32Gb class 10 card and “knock on wood” now it have not been lost on the network.
If you are runing 4.6 the settings that SOtM indicated could be a problem is if you run the setting 100BASE network speed and “auto negotiation off”. Now I run 1000BASE and “auto negotiation on” why this could make the Ultra go “bananas” I dont know…