18. (1) If the owner of a vested forest satisfies the Appellate Committee-(a) at any time after the expiry of fifteen years from the date of the notification by which the control of such forest has been vested in a Regional Forest Officer, that-(i) the control of such forest may be restored without undue risk of detriment to its conservation, and(ii) the cost of its management as determined under the provisions of sub-section (1) of section 16 has been recovered in full, or(b) at any time after the expiry of thirty years from the date of such notification that the cost of management of such forest as determined under the provisions of that sub-section has been recovered,the Appellate Committee shall by order direct that with effect from a date, to be specified in such order, the control of such forest shall cease to be vested in the Regional Forest Officer: Provided that no such order shall be made in the case of any forest, whether any working plan in respect of such forest has been previously approved under section 4 or not, until-(a) the Appellate Committee has by an order called upon the owner of such forest to prepare in the prescribed manner and to submit within such period as may be specified in such order to the Regional Forest Officer a working plan in respect of such forest, and(b) a working plan has been approved in respect of such forest in accordance with the provisions referred to in sub-section (2): Provided further that no such order shall be passed regarding a forest in respect of which there subsists an order passed under sub-section (1) of section 9, unless the owners of all the forests, in respect of which the order under the said sub-section was passed, have satisfied the Appellate Committee that there will be no undue risk of detriment to the conservation of any of such forest if the control of the said forests ceases to be vested in the Regional Forest Officer. (2) When the owner of a forest has been required under the first proviso to sub-section (1) to prepare and submit a working plan in respect of such forest, the provisions of sections 3 and 4 shall apply to such working plan as if such owner has been required to prepare such working plan under sub-section (1) of section 3. (3) The fact that the control of any forest has ceased to be vested in a Regional Forest Officer shall not operate to revive any right which may have been extinguished or modified by a proclamation under section 28.