Originally Posted by
ijgordon
Award tickets are refundable; there is a $150 fee to redeposit the miles ($25 for the second award going back to the same account); this is only waived for Executive Platinum. But date and time changes are free for anyone, so those tickets could be used another time for no fee, as long as it's the same origin/destination.
Note that you can put the award tickets in limbo so you don't have to make your mind up about when to use them. They are valid for 12 months from issue so if you want to redeposit the miles you have to remember to do it before they expire.