Fed up with going to the supermarket and finding a great promotion listed but the shelves are empty cause all the stock got snapped up before you arrived. Well Tesco don't advertise it but they run a promotion promise voucher scheme at customer services. If they are having a popular promotion e.g. 1/3 off pampers Jumbo nappies and they have no stock you can ask for a voucher which will allow you to buy six items at the promoitonal price when stock arrives even if it has reverted to its original price. Doesn't appear to be a time frame I used a voucher 6 weeks later to save £22 off nappies. It will work for any promotion except some of the really special deal such as when they run things like 25% off all wine.