I've been lurking the forums for a while decided to sign up and join the convo. Preordered 7+ 128gb in reg. black at 3:30 AM Pittsburgh time. 9/23-30 shipping window. Haven't heard anything since.
Wouldn't be too unreasonable to suggest that regional distribution centers are doing the processing hence why everything is all over the place.
As for the supply of these iPhones I did a bit of math to get a rough number of how many we may be dealing with. One report online suggests a 747 can carry 195k iPhones (6), if say 5 planes travel to Louisville every 12 hrs as we have seen, that's about 2 million a day (8 million from Monday-Thursday)... UPS FlightAware data for iPhone 7 goes back to Aug 31st, so if (and that's a big if) they've been shipping consistently since then 30 million iPhones potentially are in the US. I believe the 6 or 6s preorder was 13 million over 4 days (not sure) and if the reports are true about how big this preorder is, these figures might be like 16+ million...
TLDR there's a chance that they actually only have half the total supply they need for demand.... just my thoughts