in the event of interlocutory revision or where the Board of Appeal deems an appeal to be allowable, if such reimbursement is equitable by reason of a substantial procedural violation, or
(b)
if the appeal is withdrawn before the filing of the statement of grounds of appeal and before the period for filing that statement has expired.
(2)
The department whose decision is impugned shall order the reimbursement if it revises its decision and considers reimbursement equitable by reason of a substantial procedural violation. In all other cases, matters of reimbursement shall be decided by the Board of Appeal.
[89]See decision of the Enlarged Board of Appeal G 3/03 (Annex I).