(1) Despite section 17(2), a casual vacancy in the office of a councillor (but not a mayor elected by the electors) is not to be filled if a constitutional referendum has approved a reduction in the number of councillors but the reduction has not yet taken effect.
(2) However, subsection (1) does not authorise a vacancy to remain unfilled if the vacancy will result in the council having less councillors than the reduced number approved by the constitutional referendum.
(3) Subsection (1) applies to a casual vacancy whether occurring before or after the commencement of this section or before or after the constitutional referendum.