(a) If an assessment has passed and the assessments have been levied annually for the period set forth in the call for the referendum, then the agency that conducted the referendum may call and conduct another referendum during the last year of the assessment period, on the question of an annual assessment for the next 5 years.

(b) If a proposed assessment does not pass, then the agency that conducted the referendum may call another referendum the next succeeding year, for the purposes set forth in this subtitle, on the question of an annual assessment for 5 years.