Cal. Pub. Util. Code § 50099

Notwithstanding anything to the contrary in Section 50098, until such time as the district has operated, controlled, or used facilities or parts of facilities for providing the inhabitants within the boundaries of the district with transit services for a period of six months, the board may, but is not required to, appoint a general manager. A general manager appointed during such time holds office at the pleasure of the majority of the board.