15(1)The determination of a question referred to the Special Commissioners under paragraph 12 is binding on the parties to the referral in the same way, and to the same extent, as a decision on a preliminary issue in an appeal.E+W+S+N.I.
(2)The determination shall be taken into account by the Inland Revenue—
(a)in reaching their conclusions on the enquiry, and
(b)in formulating any amendments of the self-certificate required to give effect to those conclusions.
(3)Any right of appeal under paragraph 35 of Schedule 10 (appeals against assessments etc) may not be exercised so as to reopen the question determined except to the extent (if any) that it could be reopened if it had been determined as a preliminary issue in that appeal.