We occasionally issue coupon codes to be used for select events. We cannot issue a refund for the difference in price if you register for an event before the coupon was issued or after it expires. The coupons are time sensitive and are good only during the time period from when they are issued until their expiration date. This also applies to sales prices for events. Coupons and sale prices often are for a very limited time (sometimes less than one day or for just the first few people who utilize the coupon code).