Due for an upgrade and ready to pull the trigger? We have some good news for you. Wirefly is offering a limited-time promotion for Verizon customers looking to upgrade into a 4G LTE handset. Starting today and running through May 24, any new activations or qualified upgrades will get a $40 credit on a future wireless bill. The limit is set at five so if you have some family members that have upgrades available you should act quick before the promo expires.