You must wait until contract end. You can pay full price now, or even use a low interest credit card, but you cannot use the device payment plan while on contract.
IF you are offered an Early Device Upgrade you must turn in your phones to cover the ETF for the breach of contract. However, this route rarely goes unpunished. Once you ship off your phones you are on the hook for upwards of $300+ if the phones returned do not meet the exact specifications of what Verizon considers "perfect condition." The process takes several weeks between shipping, receiving, inspection, and approval. Meanwhile you have new phones and are bound to pay for those in full, and if anything amiss arises, you have a double cost for phones considered damaged, non-returned, or not-as-specified. Also, you have one choice of phone, not your choice, Verizon's choice. As of late, that single choice is the Droid Turbo. It is my opinion that you wait out the 2 months to begin fresh with new plans and device payment agreements. This will save you so much headache, allow time for new devices to pick from to be released, and will allow you to skip the contract upgrade and save you money over 24 months. The possible early upgrade contract can set you back a fair amount of money over going to a non-contract plan. The contract line is $40 access fee each, the new plans are $20. Contracts also have a $40 upgrade charge each. I would consider NOT opting for any upgrade or extension. I would remain within the guidelines of the terms originally set within the contracts and finish one before starting another agreement of any kind.