I just tried to upgrade, lease, and even purchase one from Dish with no success. I was informed by two representatives that a customer is only allowed to "upgrade" once a year. I upgraded two of my receivers last month, making me not eligible.
I learned my lesson with buying a receiver. Paid $550 for a 721 and look what happened to that one. They send you a replacement LEASED receiver and no matter how much you fight with them, they demand it to be a leased receiver. At least they still waived the DVR fee. No more paying that much for a receiver EVER again. Around $100 is my limit.