I got the iPhone 5 last year at launch, so I was expecting to pay AT&T's earlier upgrade price, which was usually $200 less than full retail. However, I got conflicting dates depending on what method I used to check my eligibility.
If I did *639#, the text I received said I had to pay full retail or wait until September 2014 for an upgrade.
If I used the 'Check Eligibility' link on the Apple site, I see I can get an early upgrade on October 15th, 2013, which as I expected was $200 less than full retail.
But out of curiosity, I checked the Apple Store App which has an eligibility function, and it said I was able to get an early upgrade on September 15th, 2013, in time to buy the 5s at launch. I then called AT&T to see which date was correct and was assured September 15th is when I can get the early upgrade price.
I'll admit I enjoy getting a new device at launch, so this was good new. I hope this info helps others who might be in a similar situation.