I have a 64 GB 6 Plus on AT&T Space Gray still stuck in processing. Funny thing is my friend (I placed his order under my Apple ID, diff AT&T account) ordered the same exact model as me, lives in the county next to mine, and has his preparing for shipment too.
And I placed my order at 3:22 EST. I was one of the few that got my order in the first wave of people using the Apple Store app. Delivery date is still 9/19 however!