My story is very similar to many of yours. I woke up a few minutes before 3:00 a.m. EST planning to order through the Apple Store only to find out it was having issues opening to public on certain devices from what it seems. I quickly opened up a second tab and resorted to pre-ordering through AT&T while constantly refreshing the Apple Store. I watched the countdown on the AT&T website until it finally let me log in.. Once I got in, there was 0 lag, smooth as usual and I placed an order for my other line instantly thinking that the gold iPhones overall would backorder out much quicker than the Plus. Oh boy I was wrong. Successfully pre-ordered the iPhone 6 64 GB in Gold exactly like 2 minutes into the AT&T opening to public. As soon as that finished, I got kicked out of the website for whatever reason and spent like 3 to 5 minutes attempting to get in from multiple devices with no success, once I got in, I pre-ordered my iPhone 6 Plus 64 GB Space Gray with no problems. I had more issues getting into the website than navigating through the website.
Received confirmation email 6 hours later for both orders. The line with the iPhone 6 upgrade also received the confirmation text before I did. Of course that iPhone 6 is estimated to arrive this Friday as per the confirmation email and other sources (read below.) Off the bat my shipping estimate was within 10/13 to 10/21 range I believe and now it dropped to 10/2 to 10/13.
I'm also a UPS My Choice member and see the tracking number and estimated arrival of the iPhone 6 for this Friday but nothing for my iPhone 6 Plus. That package is coming from Memphis, TN. It's good to note that the AT&T website doesn't have the tracking number listed for the iPhone 6 yet either and both orders are still "Preparing to ship".
I was thinking of running my luck and going to my local AT&T store down the road early to see if they happen to have the iPhone 6 Plus in stock in general. 64 GB+ at least and Space Gray. If they do, I hope they're able to reverse my upgrade for my line alone and do the upgrade in store.
Meh, wishful thinking?