when does t mobile gs4 get the 4.3 update?

... Not to forget the decrease in battery life. Normal use I used to be at 60%on the way home from work. Now I am 30%.

Posted via Android Central App
 
I've got a T-Mobile Samsung Galaxy S4 and have received notification of the update. Before I do it though, I have an important question...after the update is installed, does anything revert to default settings? For example, are all apps still there, wallpapers, homescreens, backgrounds, contacts, custom ringtones, etc....??? I really don't want to have to reconstruct my phone post-update. I like it the way it is now and don't want to have to start from scratch.
Also, has there been any downside(s) to upgrading to 4.3 that anyone has noticed?

Thanks in advance for any assistance.
 
Shouldnt I have the update by now? Or does february still seem like a legit timeframe? (Washington state)
 
I never got alerted that the update was available, I manually ran the update yesterday and the option was there. (Houston, TX)