Which Factory Unlocked Model works with AT&T?.

I really want this phone but refuse to buy the branded AT&T but would still like to get 4G/LTE signal. Are these models the same as the normal S6 Edge in regards to the last letter of the model. I've been having a pretty good run with the G925F and its signal would (F) and (I) S6 Edge+ support AT&T LTE bands?.