Jarahawk said:
I think you should do it. Keep in mind that your contract end date and your upgrade date are not typically the same date. Generally if one is on a two year contract Verizon 'allows' you to upgrade after twenty months. If your upgrade date is December 3 then your contract end date may be March 3. Sign into My Verizon and check before you port your number out to Sprint. As a last resort, if you are not familiar with My Verizon then you may want to call. Hopefully you can get it from the automated system. I really dislike talking to Verizon reps unless absolutely necessary these days.

I checked My Verizon and it shows that my contract expires April 3, 2013. So that means I would have to wait until that time to leave VZW. But I may decide to get another phone because I don't like this replacement phone of the HTC Thunderbolt, before December 3, 2012 upgrade. I can keep the unlimited plan for a little linger until I decide if I want to leave VZW