Yep, the nodes aren't set to run indefinitely during a power failure. Plus i suspect the times you do lose internet without losing your power, is when the network hardware is being updated/replaced and they just pull the plug to do it.
Redundant Internet
My power went out last night for about 5 hours. Despite my network hardware being on a UPS, the Internet service went out anyway. Seems they use the same power feed my house does. When the power came back on late last night the Internet did not.
This used to be routine, then they fixed it, now we are back to unreliable.
As a result I’m investing in an inexpensive edge router and getting TMobile home internet as a fallback. The long term reviews for Tmobile home Internet were mixed. At first users loved it, then after a couple of months the performance seems to have deteriorated significantly. Hopefully it is now better an with a little luck I won’t have both go out at once.