My bad. Page 38 (9.24):
When a consumer is pursuing a repair or replacement remedy to a breach of CRA, a dealer must “bear any necessary costs incurred” in carrying out the remedy. This would include the cost of returning the vehicle to the garage. Note that the provision excluding the cost of returning a car to the garage in the event of rejection (see paragraph 9.18 above) does NOT apply where a repair or replacement is being sought. Instead the remedy must be supplied “free of charge”.
True, it’s not the law but it’s from a website backed by Trading Standards and the Government and is intended to provide guidance to businesses and individuals around (in this caes) the interpretation of the CRA 2015.