The salary of a member of Council shall be twelve hundred dollars ($1,200.00) per year for the first term beginning December 1, 1971. For the terms thereafter the Council may determine and fix the salary of its members, but the salary of a member of Council shall not be increased or decreased during the term of office which he is serving. If the Council determines to change the established salary of members in respect to a succeeding term of office, such change must be made by the Council before the first day of July next preceding a regular Municipal election. Unless and until the salary is so changed, it shall remain as last fixed.