8(1)The Secretary of State may in a notice under paragraph 5 or 6(2) require the person to whom it is sent—U.K.
(a)to deliver up the licence within such reasonable period as is specified in the notice, and
(b)on doing so to pay an amount equal to the monthly duty shortfall for each month, or part of a month, in the relevant period.
(2)The “monthly duty shortfall” means one-twelfth of the difference between—
(a)the duty that would have been payable for a licence for a period of twelve months if the vehicle had been correctly described in the application, and
(b)that duty payable in respect of such a licence on the basis of the description in the application as made.
For this purpose the amount of the duty payable shall be ascertained by reference to the rates in force at the beginning of the relevant period.