Quick update: I had an email chat with TP-Link support, they are extremely helpful and professional, but unfortunately I'll be waiting for a firmware upgrade. Although I'll probably see if I can find...

Does anyone know if there has been any progress on this. I just bought a 3420, and find that I cannot get it to communicate with my EE L800 4G Dongle. The dongle is active and connected, but EE does...