Yesterday, it started acting up again and continued for several hours. Reboots did not resolve it, so I shut the antenna and router down overnight. Started everything up this morning and immediately saw the same pattern of disconnect/reconnecting. I monitor the connection here:
My Network > Network Connections > Broadband Connection (LTE) > LTE Status
You will find 4 PDN Connections, one named VZWINTERNET. The status will cycle through connected, disconnected, in_process repeatedly, and each time it will acquire a new IP address.
Mine went through this process for two hours even after two soft reboots of the HBA. While monitoring the status, I called into tech support to check on my ticket and, I kid you not, as soon as I pressed 3 for tech support, it connected and remained connected throughout the call and continues still. The support specialist and I compared it to taking your car into the dealership for a strange noise only to have it run perfectly until you pick it up and drive it away. I think it's mocking me! 
Anyway, based on the timeframe in which my troubles started, he suspected it might be something to do with the nationwide firmware update that went out recently. I have read others mention this as well.
Yes, it is frustrating, but often we are accustomed to the immediacy of results that technology gives us and we lose patience in the time it takes to correct a flaw. He assured me there is little doubt that I can expect a bill credit once this is resolved based on my personal situation. I'm confident it's just a matter of time before this gets fixed. Hang in there.
A couple weeks ago, I received an email from vzw requesting the router and cantenna logs. The service was working fine at the time, so I decided to wait until it acted up again. A few days later, I experienced a weekend-long downtime. It has been almost a week since I sent the logs and I haven't heard back yet.
In the meantime, I have developed a new strategy for responding to the cantenna seizures by logging into the router and performing a soft reboot of the cantenna, repeatedly, until the connection finally stabilizes.
Advanced > HBR Advanced Settings > (Yes) > Reboot HBA
Sometimes it takes several attempts; sometimes just one or two. Soft reboots don't take as long as performing a hard reboot, so since I plan on having to perform multiple reboots, I'd rather do it from the comfort of my couch.
However, with each episode, I am getting increasingly frustrated, but it's either wait it out with HomeFusion, switch to satellite (no way), or go back to my homemade 4G antenna setup that will cost me $50/month more for the same data, plus fighting to get out of the contract without termination fees. 
I am hanging on with the expectation that I will get credit for the months that I have not had reliable service.
It seems my HBA has developed a case of Monday mono. This is the third Monday in a row that I have spent several hours trying to get a stable connection. This is getting annoying. This wide scale service issue has been causing problems for at least 3 months now. Is this ever going to get fixed?! I used my own, reliable $300 antenna/router/wireless modem setup for years before Home Fusion came out here, but the service cost difference is too great to consider switching back. It's a shame that what is probably a much more expensive hardware setup can't accomplish what consumer-grade electronics had no problem with. 