4Where a Chapter I or Chapter II landlord is incapable by reason of mental disorder (within the meaning of the [1983 c. 20.] Mental Health Act 1983) of managing and administering his property and affairs, then for the purposes of Chapter I or (as the case may be) Chapter II—
(a)the landlord’s receiver appointed under Part VII of that Act or Part VIII of the [1959 c. 72.] Mental Health Act 1959, or
(b)(if no such receiver is acting for him) any person authorised in that behalf,
shall, under an order of the authority having jurisdiction under Part VII of the Mental Health Act 1983, take the place of the landlord.