Use LG Bridge to preform the update. That will connect to The Mobile and grab the correct file for your device.
You won't need to grab a file you're not sure about. Also, your phone won't be reset.
The OTA should be available yesterday/today, according to @askdes from T Mobile. It may not be available to your device just yet.
I just connected my phone and checked for updates, using LG Bridge. Took about 15 minutes with a 2.81 GB file. Not wipes or resets, just an in-place update. No resetting apps either. It just works!