24.—(1) If at any time any licensed supplier has reason to believe that the payment, or the aggregate of the payments, made in respect of the levy by him in respect of a qualifying month pursuant to these Regulations is greater than it should have been, he may serve notice on the Director setting out–
(a)his reason or reasons for the belief; and
(b)the amount which he believes he should have paid and the manner in which that amount has been calculated.
(2) If the Director wishes to question any matter set out in a notice served on him under paragraph (1), he shall do so by notice served on the licensed supplier within 28 days of receiving the notice served under paragraph (1).
(3) Any notice served under paragraph (2) shall set out in full the Director’s reasons for wishing to question any matter in the notice served on him under paragraph (1).
(4) If the Director fails to serve a notice under paragraph (2) within the period mentioned in that paragraph, he shall be deemed to have accepted the notice served on him under paragraph (1) without question as to the amount (but without prejudice to the ability of the Director subsequently to serve notice on the licensed supplier in accordance with regulation 17 in respect of the qualifying month in question) and the licensed supplier may then deduct the difference between the amount which he has paid and the amount set out in that notice (together with an amount in respect of interest in accordance with regulation 29(2)) from the next payment due from him under paragraph (3) of regulation 11.
(5) No notice under paragraph (1) may be served after the expiry of a period of 3 years commencing on the last day of the qualifying month in question.