Originally Posted by mbreuer

Depends... if they're fully refundable, for example, then there should be no issue. Assuming what you're planning is OK wrt the fare rules, then you should call the airline. While the coupons may retain their value, your reservations will probably be cancelled. In some cases, i.e., "refundable" but restricted fares, you can re-use the coupon w/o penalty, but only if you cancel/change the affected flights first.