79.—(1) Where interest is payable in accordance with regulation 76 it shall be remitted for the period commencing on the first relevant date and ending on the second relevant date in the circumstances specified in paragraph (2).
(2) For the purposes of paragraph (1), the circumstances are that the liability, or a greater liability, to pay interest in respect of a Class 1A contribution arises as the result of an official error being made.
(3) For the purposes of this regulation—
“official error” means a mistake made, or something omitted to be done, by an officer of, or person employed in relation to, the Board acting as such, where the employer or any person acting on his behalf has not caused, or materially contributed to, that mistake or omission;
“the first relevant date” means the date defined in regulation 76(5) or, if later, the date on which the official error occurs; and
“the second relevant date” means the date 14 days after the date on which the official error is rectified and the employer is advised of its rectification.