12.—(1) Article 22 of the principal Order (provisions supplementary to Articles 20 and 21) shall be amended as follows.
(2) After paragraph (4) (power to substitute percentage mentioned in Article 20(4) or 21(1)) there shall be inserted the following paragraphs—
“(4A) In paragraphs (4B) and (4C) “existing agreement”, in relation to an order under either of those paragraphs, means an agreement under Article 21 which is in force on the commencement of the order under that paragraph.
(4B) Where the Department makes an order under paragraph (4), the Department may by order direct that for any percentage specified in an existing agreement there shall be substituted such other percentage as may be specified in the order under this paragraph.
(4C) The Department may by order direct that for any percentage mentioned in an existing agreement in respect of a hereditament of a class specified in the order there shall be substituted such other percentage as may be specified in the order.
(4D) The power conferred by paragraph (4C) is exercisable whether or not it is exercised in consequence of an order under paragraph (4).”.
(3) In paragraph (5) (orders subject to affirmative resolution and date of commencement), after “(4)” there shall be inserted “, (4B) or (4C)”.