It would be covered by The Consumer Protection (Distance Selling) Regulations 2000.
Which would actually mean you are not entitled to cancel and are not entitled to a refund under section 13(c)
"13.—(1) Unless the parties have agreed otherwise, the consumer will not have the right to cancel the contract by giving notice of cancellation pursuant to regulation 10 in respect of contracts—
(a)for the supply of services if the supplier has complied with regulation 8(3) and performance of the contract has begun with the consumer’s agreement before the end of the cancellation period applicable under regulation 12;
(b)for the supply of goods or services the price of which is dependent on fluctuations in the financial market which cannot be controlled by the supplier;
(c)for the supply of goods made to the consumer’s specifications or clearly personalised or which by reason of their nature cannot be returned or are liable to deteriorate or expire rapidly;
(d)for the supply of audio or video recordings or computer software if they are unsealed by the consumer;
(e)for the supply of newspapers, periodicals or magazines; or
(f)for gaming, betting or lottery services."