At the expiration of the term of office of the President of the Cherokee County Commission, the office, power, and duties of such officer shall be invested in the chairman of the commission. The Judge of Probate of Cherokee County shall be the chairman and shall have all the duties and powers of that officer as prescribed by Sections 11-3-1 through 11-3-26, all of which relate to the county commission. Such duties shall be in addition to any and all other duties prescribed by law for the Judge of Probate of Cherokee County for which he or she shall receive a total salary as chairman and judge of probate in the sum of at least forty thousand dollars ($40,000) in accordance with Section 12-13-20.