I also have ATT 256GB Black 7+, originally had delivery date of 9/23 - 9/27. I got the notification that it shipped yesterday. UPS originally had delivery scheduled for tomorrow (Tuesday), but they just bumped it back to Wednesday a few minutes ago. :0
I've got the same one pre-ordered. Originally, it had a "Delivers" date range of 9/23 - 9/27. The status was updated from "Preparing for shipping" to "Shipped" early yesterday morning. The current tracking at the Apple site says that the est delivery is 9/22, yet when I check the tracking on UPS, it said that the est. delivery is tomorrow (although the location scan says that it's still in China).
Nice. That is re-assuring. I hope mine goes from processing to preparing to ship soon.