S.C. Code § 5-5-10
The forms of municipal government in this State shall be as follows:
All municipalities shall adopt one of these forms in the manner prescribed in this chapter.
The selection shall be made by ordinance of the municipal council after at least one public meeting. The form selected shall be the form most nearly corresponding to the form in effect in the particular municipality on March 1, 1974, as determined by the municipal governing body; provided, however, that those municipalities which adopted a new form of government through a referendum after March 1, 1974, and prior to June 1, 1975, shall adopt the form selected by the referendum.
If a municipality failed to adopt one of the above forms of government within fifteen months of December 31, 1977, it shall be considered to have forfeited its articles of incorporation, until such time as the municipality adopts one of these forms of government and certifies the adoption to the office of the Secretary of State. Upon certification by the governing body of the municipality of the adoption of one of the forms of government to the office of the Secretary of State, the articles of incorporation for the municipality shall be reinstated. All actions taken by the governing body municipality during the period of forfeiture shall be deemed to have been ratified by the governing body of the municipality upon reinstatement of the articles of incorporation. The reinstating municipality must not be contiguous to any existing municipality.
S.C. Code § 5-5-10