Here are the T-Mobile (USA), G900T, firmware details and download for Marshmallow, Android 6.0.1.
Model SM-G900T
Model name GALAXY S5
Country USA (T-Mobile)
Version Android 6.0.1
Changelist 7500527
Build date Thu, 05 May 2016 07:17:09 +0000
Product code TMB
PDA G900TUVU1GPE1
CSC G900TTMB1GPE1
Model SM-G900T
Model name GALAXY S5
Country USA (T-Mobile)
Version Android 6.0.1
Changelist 7500527
Build date Thu, 05 May 2016 07:17:09 +0000
Product code TMB
PDA G900TUVU1GPE1
CSC G900TTMB1GPE1