The Planning Commission shall consist of the Mayor or a person appointed by him/her to act in his/her stead as his/her deputy, one (1) member of Council to be selected by the Council for such term as it shall determine, and three (3) electors of the City not holding other municipal office or appointment. The terms of the present members of the Planning Commission shall expire on December 31, 1951. The three elector-members shall be appointed by the Mayor, with the concurrence of a majority of the members elected to Council, for terms of six (6) years each, except that of the three elector-members appointed for the term beginning January 1, 1952, one shall be appointed for a term of two (2) years, one for a term of four (4) years, and one for a term of six (6) years. A vacancy occurring during the term of any member of the City Planning Commission shall be filled for the unexpired term in the manner authorized for an original appointment.