EM-12g and ATT loses connection every day. This is repeatable with two different routers, and diverse Sim cards. I have updated the firmware on both routers with no affect.
I have heard about this forum from the LTE hacks forum. No one had any answers and I tried every suggestion.
I don’t know if there is a firmware that address this?
I don’t know how to check my current firmware. I bought one from eBay and one from LTEfix.
Some recommended qflash and a file. Others have recommended an OTA solution with a ftp server.