pc world say:
"Replacement product if your PC or laptop can’t be fixed:
If your product can’t be fixed, or it takes longer than 6 weeks to repair, you may request a replacement PC or laptop.
The replacement may be a fully refurbished product, or in the form of vouchers to purchase a new product of at least the equivalent specification.
If your product is replaced, your PC Performance Service Agreement ends and you will receive vouchers for the remaining value. You can use these vouchers when you next buy PC Performance."