Here is what I currently know about the At&t ZTE Mobley:
1) Fact -- Firmware VM6200V1.0.1 has a new "No Time Out" option
2) Apparently, AT&T controls when new firmwares are pushed to the devices. There is no way for you to manually update it.
3) Fact -- ZTE Mobley with firmware VM6200V1.0.1 will "hang" or "freeze" after 1-2 days of continuous operation. The device is still powered on, you can still "see" the WiFi network but you can't connect to it.