Where to find new firmware

Running version 1.2003.03.0178 on the T-Mobile GW but I am not sure when this upgrade took place. It may have been pushed when I did a factory reset on the unit about 3 weeks ago. I am not sure it is super stable as I see random signal drops for both the primary and secondary signals with the tower and the signal strength, quality and signal to noise ratio are all in the good to excellent range. So, an upgrade to version 1.2003.03.0178 might be possible but not sure if it is the holy grail.