Will T-Mobile have nano-sim cards when the new iphone comes out?

I want to buy an unlocked new iphone when it comes out and use it for T-Mobile, but since the new iphone will most likely be using nano-sim cards. I want to know if T-Mobile will have nano-sim cards by the time the new iphone is released.

Well, if tmobile doesn't have the iPhone, why would they have nano sim cards for the iPhone? I don't think they will

Yes- Already have them. Many phones use them now.