R8000 — Nighthawk X6 AC3200 Tri Band WiFi Gigabit Router

After the last 2 firmware updates, experiencing problems with wifi and cabled connections dropping repeatedly for Windows 10 notebooks, android phones, the internet connection is via an LTE radio (rural network), unknown for Apple devices, as they are not consistently connected to this network. The same devices are being used in another physical location (10KM away) and are working fine on a different Netgear router (operating as an access point on a COGECO cable network). Done all the usual troubleshooting, reset to factory, etc, internet supplier (NWIC) was out to test, the connection from the radio to the Netgear router is stable. Any insights on what to test for would be appreciated.