Keep this in mind... Premier customers have several outlets to order from. As a premier customer I have a company site that is specific to my company with discounts applied to certain items. I can order on the premier web site with no human intervention... I can call my order into Premier customer care, I can call Business Key contact and place my order, or I can email/call my dedicated account executive and place my order. It's all relative in the end, it all comes from the same inventory. Only difference, when you call Business Key contact, Premier Care, or your dedicated account executive you can bill the device total to your account, where-as direct online orders require a credit card to complete, there is no option to bill the purchase to your account. It's how you track your order that is different. Premier online and call in orders get tracked on the premier specific site, all other order methods are tracked at wireless.att.com/order_status.
I have never once been told that AT&T will give any type of priority to Premier or new customers vs. upgrades or add-a-line orders as the inventory all comes from the same place. I can tell you for a FACT this exact same issue happened with the iPhone 4 pre-orders. I ordered on our premier web site and got the back ordered status until the day it actually shipped. It went from back ordered to shipped with a tracking number with no updates in between.
I think AT&T is really having a hard time keeping up to date with the change in availability and quite possibly all the pre-orders. Makes you wonder if the demand has exceeded the available initial stock?