Hi,
This is a customer care coupon for $25 off a rt of $75 to $199, $50 off a rt of $200 to $299, etc. (Promotion Code CKDE).

Looked in the FAQ and all around some old threads on these Continental Coupons, but can't find the answer to this:

Looks like I need to apply this on the payment page for a ticket. What happens if I find a better itinerary within 24 hours, do a free cancel and rebook, will my coupon still be good or is lost?

Or for that matter, if i have to rebook later on, paying a change fee, is the value of the coupon still applied, or is it loss in the process of rebooking?