When will the iPhone 6s be available through T-Moblile?

As far as I know there isn't a confirmed date but is there an estimate?

Um usually 7 days after the pre orders are shipped you better be lined up usually after iphone launchs all the carriers stock empty

Those questions will probably be answered in 2 days when Apple unveils it.

18th September is the expected date, following the pre-order from the 11th & the announcement on the 9th.