The above post is correct, From the Disney Visa Card Website:
Reward Dollars Expiration:
Your Disney Dream Reward DollarsSM are good for a full five years (60 billing cycles) from the time they're earned, while included in your Program Rewards Balance. There are no block-out dates. Please refer to the Guide to the Disney RewardsSM Program for complete program details, including Terms and Conditions.
Once reward dollars are transferred to your Disney RewardsSM Card, the reward dollars are available for redemption until the expiration date on the rewards card. Rewards cards, and the reward dollars remaining on them, expire December 31st of the year after the year when the card was first ordered. For example:
A card ordered October 1, 2003, will expire on December 2004.
A card ordered January 1, 2004, will expire on December 2005.
When the card expires, any remaining reward dollars on the card will be forfeited. You will then need to request a new card. Replacement cards are not automatically sent to you.
Once reward dollars have been transferred to a rewards card, you cannot transfer them back into your Program Rewards Balance. Therefore, we recommend that you transfer only the number of reward dollars you plan to redeem prior to the expiration date of the rewards card.
Reward Transfer Rules:
You must transfer at least twenty (20) Disney Dream Reward DollarsSM from the Program Rewards Balance the first time you request a Disney RewardsSM Card. If you are requesting transfer of Disney Dream Reward DollarsSM from the Program Rewards Balance to a previously issued Disney RewardsSM Card or requesting issuance of an additional Disney RewardsSM Card, all such transfers/issuances must be in increments of at least ten (10) or more Disney Dream Reward DollarsSM.