Sucks! As someone who's also afflicted by Verizon, I'm truly sorry to hear that.
Well, if you want to exhaust all options, try disabling UPnP and turn off the auto check for new firmware if you think that might be related.
If the UPnP toggle fails me, I'll buy another router and contact Verizon to have ethernet provisioned. Don't really see any further options at this point. Think we've tried just about **bleep** near everything.
Going on 27 hours since last reboot, btw.