Nothing contained in this article, except as specifically provided, shall affect or impair the rights or privileges of officers or employees of the municipality or of any office, department, board, or agency existing at the time when this article shall take effect, or any provision of law in force at the time when the mayor-council form of government shall be adopted and not inconsistent with the provisions of this article, in relation to the personnel, appointment, ranks, grades, tenure of office, promotion, removal, pension and retirement rights, civil rights, or any other rights or privileges of officers or employees of the municipality or any office, department, board, or agency thereof.