Very similar symptoms. here's my commiseration. I'm undecided as to how to proceed.
I had a Rev F router that a very friendly, competent Vz tech left for me after a visit for an unrelated problem. It's worked fine for several (2+) years. A few months ago I had a day filled with FiOS internet access problems. Phone was fine. TV was ok, except no VOD on any of the STBs. After powering down everything in the house from the ONT (removed the battery too!) to the router, STBs, and PCs multiple times and restarting from the outside inward, I gave up and called Vz support. The (exceptionally clueless?) tech put me through the usual power down/up drill again twice and then declared my router needed replacement. C'est la vie. While I disagreed, I knew arguing was senseless. She put in the order for a replacement to be shipped. That was a Thursday night. I was told it wouldn't arrive until Monday or Tuesday because of the weekend. Since I work at home 3 days a week (M-W-F, lucky me) it would mean making an hour drive into my office(unlucky me) until it arrived. Friday morning before heading out, I crossed my fingers and tried connecting. It worked (again, lucky me.) No problems resurfaced that day, or through the weekend - even VOD came back. When the replacement router arrived Tuesday, it was a new Rev I. While happy, I was reluctant to install it and lived with the old one for another week. I gave in and swapped them, sending back the old one.
As I mentioned, I work from home 3 days a week. I follow the same "work from home" routine on those mornings. 1) reboot my ethernet-wired PC; 2) go get my coffee in the kitchen and let the dog out; 3) about 10 minutes later I start my VPN; 4) I start a Remote Desktop session to my office machine. Up to here, that's been the same for years and aside form that one terrible day, there's been no problem worth mentioning. After connecting the Rev. I all was good as well. However, for the last 2 weeks, when I go through that routine and reach #4, to start the Remote Desktop session, the Rev I spontaneously reboots; just a red light, and then the green lights start and begin to flicker on/off during rediscovery & recognition on the Vz network. While that progresses, I close the not-connected RDP start-up window, and terminate the VPN which is stuck trying to "reconnect". I wait until full internet access is restored. Then I start the VPN. I start the RDP. All is good. If I happen to shut down the RD & VPN during the day, and then restart a connection to work, it connects fine without the router reboot happening. But the next time I try a "morning" attempt 2 or 3 days later, it goes through the same problematic reboot-upon-RD scenario.
While most Vz techs I've dealt with are very good, I live in fear of getting another clueless tech and figure the "devil I know is better than the one I don't". But reading this poster's problem is making me think it isn't "just me". I'm interested in hearing if others are having similar issues.