Yes, it sure takes some patience when each session of troubleshooting takes 8-10 days. The Rocket Hub has great potential for remote monitoring for only $10 per month. I am also able to turn the furnace up and down remotely when it is working.
After posting yesterday, I spent a very long time on hold for Rogers support but I eventually talked to Dominic and he didn't just want to move on to the next caller. He spent a good amount of time discussing the situation and suggested a 12 second reboot. Hold the power button down for 12 seconds to power off and reboot the ZTE. It seems to be an undocumented procedure and it appears to force the ZTE to get a new IP address. So now I am running the arduino and it is doing a 12 second (actually 12.5 second) reboot of the ZTE every 12 hours. So - wait 10 days and I will let you know how it works out.
As for changing the Network Selection to 4G only, it is set to auto and the selections are greyed out, so I assume a user can't change that. I would also doubt that is a factor as it is very reliable for those 8-10 days and then totally disconnects. Thanks.