10Where the valuation officer notifies the amount of a rateable value to the rating authority in respect of a Gas Board in accordance with paragraph 8 of this Schedule—
(a)the rating authority, in making and levying any rate for a rate period to which the notification relates, shall include the Gas Board as the occupier of a hereditament of that rateable value ; and
(b)the valuation officer, at or as soon as may be after the beginning of the year consisting of or comprising any such rate period, shall cause such alterations (if any) to be made in the valuation list as may be requisite for showing the Gas Board in the list as the occupier of a hereditament of that rateable value ; and if any such alteration is made after the beginning of the year, it shall be treated as having been made at the beginning of the year:
Provided that, if the year referred to in sub-paragraph (b) of this paragraph is a year beginning with the date on which a new valuation list comes into force, that sub-paragraph shall not apply, but the valuation officer shall include the Gas Board in the list as the occupier of a hereditament of the said rateable value.