4(1)An appeal under this Part to the General or Special Commissioners may be brought out of time with the consent in writing of an officer of the Board or the Board.U.K.
(2)Consent shall be given if the officer or, as the case may be, the Board are satisfied—
(a)that there was a reasonable excuse for not bringing the appeal within the time limit, and
(b)that an application for consent was made without unreasonable delay.
(3)If the officer or, as the case may be, the Board are not so satisfied, they shall refer the matter for determination by the Commissioners.
(4)If there is a right to elect to bring the appeal before the Special Commissioners instead of before the General Commissioners, the Commissioners to whom an application under this paragraph is to be referred are the General Commissioners, unless the election has been made before the application is referred.