Any person holding a Class B license issued pursuant to section 39-2308 may apply to the board of examiners for a Class A license upon forms prescribed and furnished by the board upon submitting evidence that (1) he or she has been employed and appointed by one or more county or counties or municipality or municipalities as a county highway or city street superintendent on at least a half-time basis for at least two years within the past six years or (2) he or she has at least four years' experience in work comparable to street or highway superintending, on at least a half-time basis, within the past eight years. Such application shall be accompanied by a fee of seventy-five dollars. A Class A license shall be valid for a period of three years and shall be renewable for three years as provided in section 39-2308.02 upon payment of a fee of fifty dollars.