Registration as a telecommunications system controller is required of any person employed by the association representing employers of longshoremen and checkers and of the labor organization representing longshoremen and checkers in the Port of New York District, or a joint board of such association and labor organization, who participates in the operation of the telecommunications hiring system (THS). An applicant for registration as a telecommunications system controller must be sponsored by the association representing employers of longshoremen and checkers and the labor organization representing longshoremen and checkers in the Port of New York District, or by a joint board of such association and labor organization. Registration as a telecommunications system controller shall terminate upon the registrant's cessation of employment.