Interest
10(1)Rules may make provision—
(a)as to the circumstances in which the tribunal may order that interest is payable;
(b)for the manner in which and the periods by reference to which interest is to be calculated and paid.
(2)The rules may, in particular, provide that compound interest is to be payable if the tribunal—
(a)upholds a decision of the Director to impose a penalty, or
(b)does not reduce a penalty so imposed by more than a specified percentage,
but in such a case the rules may not provide that interest is to be payable in respect of any period before the date on which the appeal was brought.