I've had the dual WAN setup for 4+ years already with no major issues after several outages - until a week ago. So issues in previous discussions don't seem to apply here. The router simply got to a state that it wouldn't reboot even though the GUI made it look like it was rebooting. (my ssh...
Turns out that even a factory reset didn't work.
It looks like something got stuck in the router when Comcast was going up and down repeatedly around the new year.
The factory reset option wiped out the configuration but never actually rebooted the router. (Heck even the reboot button didn't...
I've had the dual WAN (Comcast+ATT, Failover+Failback) configuration for a number of years without much trouble but it has not been functioning properly since the rain storm last week when the primary WAN (Comcast) went down.
It now seems to get stuck in the secondary WAN no matter what I do...