(1)

(a) An undertaking shall ensure that calls automatically forwarded to a subscriber's terminal as a result of action by a third party shall, without charge upon a request being made to the undertaking by the subscriber to do so, cease to be so forwarded as soon as practicable after receipt of such a request.

(b) An undertaking that has not already done so shall inform its subscribers of the requirements of subparagraph (a).

(2) An undertaking whose network is interconnected with the network to which the line of the subscriber concerned is connected shall, within 48 hours, comply with any reasonable request made by another undertaking for the purpose of complying with paragraph (1).