In the mean time, consider setting up the WAN interface as DHCP with however you’re connecting to the Mobly. Since it’s handing out on 192.168.1.1/24 and the GL-AR300M is handing out on 192.168.8.1/24, there shouldn’t be a conflict. “Double NAT” isn’t great, but if your looking for general Internet access, it should work well enough for you. (Likely no way to get rid of double NAT without being subject to the five-device limit.)