(1) If part only of a parcel of land used or occupied solely as the site of a single dwelling-house or as rural land ceases to be so used or occupied, the council must require the Valuer-General to determine the amount of the attributable part of the land value of the land (if any) in relation to that part of the land and each other part of the land.
(2) The council must, in accordance with the Valuer-General's redetermination, make a due adjustment to the rates payable, or apply the provisions postponing rates, as it considers equitable in the circumstances.