(1) For the purposes of regulation 21 the Commissioner shall maintain and keep up-to-date, in printed or electronic form, a register of the numbers allocated to subscribers, in respect of particular lines, who have notified the Commissioner or, prior to 30th December 2016, OFCOM that they do not for the time being wish to receive unsolicited calls for direct marketing purposes on the lines in question.

(1A) Notifications to the Commissioner made for the purposes of paragraph (1) by corporate subscribers shall be in writing.

(2) The Commissioner shall remove a number from the register maintained under paragraph (1) where the Commissioner has reason to believe that it has ceased to be allocated to the subscriber by whom the Commissioner was or, prior to 30th December 2016, OFCOM were notified pursuant to paragraph (1).

(2A) Where a number allocated to a corporate subscriber is listed in the register maintained under paragraph (1), the Commissioner shall, within the period of 28 days following each anniversary of the date of that number being first listed in the register, send to the subscriber a written reminder that the number is listed in the register.

(3) On the request of -