Update:
I'm not trying loopholes right now anymore. As it turns out, in addition to the unlimited data, another one of the phones on my account has a talk plan that VZW hates so much that NONE of the 5 phones on my account can upgrade. So that's a whole different ballgame I have to figure out.
In the meantime I've talked with Asurion and the nice lady said that since we have so many accounts with them and have had them for so long, that they may be able to give me a different phone in replacement. They're calling back later after I'm done with work. If this does work, I may try to just get the best upgrade I can get. Maybe the Moto X because of the price and the specs.