Default RUU T-Mobile 4.1.2 Update

I'm looking at updating from the 4.1.2 update, but do not want to move to 4.3, why?

After upgrading to the 4.3 RUU for T-Mobile, determined that wifi-tether no longer works properly. It will not advertise an AP and only works in ad-hoc mode.

I've like to move to 4.2.2, but was hoping T-Mobile had an OTA for 4.1.2 that would upgrade the Sense interface?

Thanks.