I also resolved this issue of dropping every 5.5 hours. A cellular modem firmware update was required……not to be confused with Pepwave firmware update. Review the post at the link below.
FYI the first time I checked the console it returned a response my hardware was up-to-date. A week later it returned that an update was available. The firmware installation process took 4 tries to fully complete, which I understand is typical. Allow several hours, the installation process is fairly slow.