I'm afraid you may not be able to reclaim a upgrade becuase as it happened to me Verizon counts a new phone bought either outright or from another souce as an upgrade in which you lose the upgrade option. This happened to me already when my son had an upgrade option left of his droid and I gave him my bionic and I later decided to use his upgrade option for the galaxy s3? He no longer had the upgrade option but was pushed back a year and a half
Fukers
end of rant!
Keep the unlimited like it has been suggested