City councilmembers shall continue to hold office for the balance of the terms for which they were elected. Upon expiration of these terms, their successors are to be elected and qualified at the next biennial municipal election to be conducted as provided in Chapter 35A.29 RCW. Offices of councilmembers for position numbers 4, 5, 6 and 7 will be filled at the 1971 general municipal election for a four-year term of office. City councilmembers position numbers 1, 2 and 3 shall be filled at the 1973 general municipal election for a four-year term of office. (Ord. 610 § 2, 1971).