Tesco has changed the conditions of its price match guarantee against rival Asda in an attempt prevent shoppers using a loophole by buying items simply to get money back, which made some customers hundreds of pounds each.
Tesco Clubcard holders have complained in their droves that the supermarket's website crashed over the weekend as the deadline loomed to exchange vouchers before rewards were cut by 25%.
Tesco Clubcard customers can double the value of their rewards to spend on some non-food items at the supermarket for the next four weeks, under a scheme that launches on Monday 8 November.
Tesco is revamping its Clubcard loyalty scheme by reducing the rewards available for spending vouchers, but it will continue its 'double' offer on collecting points.