I'm with LtKen on this one. You say you're extending by 2 years. The most you can be extended is 24 months from the current day you get the phone, so in other words, you won't have a phone that is in contract any further than 12/6/2012. Lets say you got a phone on 12/6/2010 and a month later 1/6/2011 you go into Best Buy for a "free" or reduced priced phone, you will not be able to get it for the line you upgraded to on 12/6/10, and it will not extend your contract to 1/6/2014. It just doesn't work that way. You might want to sit down and really look at what you've been doing.
You are telling me I can't do what I just did. I have no upgrades on any of my 4 phones. My oldest phone is my D1, Feb '10. The Ally I bought in August '10 for $50 was destroyed in a fire. (obviously less than 2 years old) I filled out Assurion forms on-line and they would replace for $50. Best Buy gave me one for $0. On the day I got the new Ally, BB also had D1's for free, but out of stock and I needed a replacement without driving to the next city. If in stock I would have another D1 on my account FOR FREE