[MT-AU Public] EP06-E dropouts

I have an LHG with an EP06-E module fitted running to a tower about 10km away connected to Telstra. It's been OK for the most part but lately the 4G link has been flapping several times a day, sometime with long periods of silence. The logs show nothing awry apart from the LTE link going down and DHCP not happening. Has anyone else noticed robustness issue with this module? I have set system reboots at 5am to try and help but it keeps happening through the day.