Here's the official response, I actually emailed them about this yesterday:
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Hello -----,
Our billing system is set up to manage payment and pre-paid time on your account on a monthly, 3 month, or 6 month increments (or 2 months if you are using a game card). However, we are not able to "pause" or otherwise suspend account access due to inactivity or infrequent use. Once the prepaid billing cycle begins, it will complete on its set time schedule and it cannot be reversed or refunded.
However, if you need to take a break from World of Warcraft, then you can temporarily cancel your subscription so that you will not be billed further, and your account will then be suspended until you go in and manually put in a new subscription. You can manage your subscriptions on the Account Management page:
http://www.worldofwarcraft.com/account/
At this time we have no plans to delete World of Warcraft accounts or characters for inactivity, even if the subscription is discontinued. This means that if you decide to take a break from the game and suspend your account payments, you will be able to continue playing at a later time when you resume your subscription and reactivate the account. Your characters will be there waiting for you.
Please keep in mind that any changes made to your account in regards to billing information will not go into effect until the end of your billing cycle. So if you prepay for 3 months, and cancel 1 month after you have paid, you will still have 2 more months before the cancellation goes into effect.
If you have further questions or concerns regarding subscriptions or account setup, please don't hesitate to contact our Billing & Account Services team. Please email
billing@blizzard.com or call toll-free at 1-800-59-BLIZZARD (800-592-5499). Customers in Australia should call 1-800-041-378. Representatives are on hand to take calls between 9am and 6pm PST.
Regards,
Sang K
Blizzard and Account Service Representative
Blizzard Entertainment
http://www.blizzard.com
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