The one doing all the work is the csc because i am on BRA8 and i am carrier tmo and phone is tmo and i get TMB/TMB/TMBIt is weird, because T-Mobile hasn't even released their latest firmware yet. So it's definitely not TMB, just like venom0642 stated, it's AT&T Stock.
Sent from my T-Mobile Samsung Galaxy Note 8 using XDA Labs