The registration does not get overwritten when you register it. If someone registered it in July, then Apple considers that person the original owner, and there's a whole slew of steps you have to go through to transfer the registration information.
Because it was purchased from a third party, most likely the registration is showing up like that because that's when apple sold it to Micro Center.
What does Apple.com show for warranty information? It will tell you the AppleCare expiration date, which will tell you when Apple thinks it was originally purchased. If you have an Apple ID, you can log in to see your registered computer as well.
I bought a Mac Pro last year and had something similar happen. Wrong configuration, about $1k difference. Apple returned it and swapped it for the right one no questions asked.
I buy a couple hundred Macs a year for my business, so I've been through just about everything warranty related with Apple.