11.—(1) Where the conditions specified in Article 16(1) and (2) are satisfied, the Department shall pay to the compensator the difference between the amount that has been paid and the amount that ought to have been paid.
(2) Where the conditions specified in Article 16(1) and (3) are satisfied, the compensator shall pay to the Department the difference between the total amounts paid and the amount that ought to have been paid.
(3) Where the Department is making a refund under paragraph (1), or demanding payment of a further amount under paragraph (2), it shall send to the compensator (with the refund or demand) and to the person to whom the compensation payment was made a statement showing—
(a)the total amount that has already been paid to the Department;
(b)the amount that ought to have been paid; and
(c)the difference between those amounts, and whether a repayment by the Department or a further payment to it is required.
(4) This paragraph applies where—
(a)the amount of the compensation payment made by the compensator was calculated under Article 10; and
(b)the Department has made a payment under paragraph (1).
(5) Where paragraph (4) applies, the amount of the compensation payment shall be recalculated under Article 10 to take account of the fresh certificate of recoverable benefits and the compensator shall pay the amount of the increase (if any) to the person to whom the compensation payment was made.
(6) This paragraph applies where—
(a)the amount of the compensation payment made by the compensator was calculated under Article 10;
(b)the compensator has made a payment under paragraph (2); and
(c)the fresh certificate of recoverable benefits issued after the review or appeal was required as a result of the injured person or other person to whom the compensation payment was made supplying to the compensator information knowing it to be incorrect or insufficient with the intent of enhancing the compensation payment calculated under Article 10, and the compensator supplying that information to the Department without knowing it to be incorrect or insufficient.
(7) Where paragraph (6) applies, the compensator may recalculate the compensation payment under Article 10 to take account of the fresh certificate of recoverable benefits and may require the repayment to him by the person to whom he made the compensation payment of the difference (if any) between the payment made and the payment as so recalculated.