Heya,
I'm HOPING maybe this will help a few of you!
I upgrade to the Lumia 820 on 10th November and this is what my box, had a little leaflet type thing stuck on it that says
"Claim you Windows 8 Pro PC Software Update"
and inside there was a code that you have to enter in on the website, along with your IMEI etc.
ANYWAY, as I was browsing on the terms and conditions, there was a section that said:
"The offer is subject to availability. Customers are only eligible to redeem once per Nokia Lumia 820 purchased, while promotional phone stocks last. No cash alternatives in whole or in part. "
So although you have all been messed around (and I would see what you could get for that) I don't think you will be able to claim for the upgrade without the little thing stuck to it, as that indicates it is a promotional pack
ALSO, I don't know if this will help but when I spoke to the guys in Carphone, they basically explained the offer stock was only predicted to last for release weekend and anyone who got one after that would be lucky?
Hope that helps a little bit! I'm sorry you have all got messed around!