(a)
The term of office of any council member who has been elected and whose term of office has not expired shall not be affected by any change in the boundaries of the district from which he or she was elected.
(b)
At the first election for council members in each city following adjustment of the boundaries of councilmanic districts, a council member shall be elected for each district under the readjusted district plan that has the same district number as a district whose incumbent’s term is due to expire.
(c)
Notwithstanding any other provision of this article, a change in the boundaries of a council district shall not be made within 90 days prior to the final date of voter registration for an election of council members in the city or between the municipal primary election and the general municipal election.