Who sells a preorder when they can get a refund??
Presumably the pre-order is worth more than the refund value. For example, if the order was early enough, the single cost $1299, while the current price has nearly doubled. Someone who wants a single would probably be willing to pay the current new doubled price, especially if it meant a free jump to an earlier place in the line. It makes a lot more sense to sell the pre-order rather than taking a refund.