Guests have reported that Disney allowed them to apply the value of an unredeemed voucher toward the purchase of another pass, if past the required activation date.
For example, if you pay $480 (approx.) for a voucher and don't activate it by the 1/31/15 cutoff date, they will give you $480 credit toward the purchase of another ticket. However, this policy is not stated in writing anywhere. And I would not expect to get any cash refunded if the ticket you wish to buy costs less than the (approx) $480 you spent.