Cal. Health & Safety Code § 101660
(b)
(1) The board of trustees shall consist of the following nine members:
(3) Notwithstanding paragraphs (1) and (2), either during or after the formation of the authority, the board of supervisors and each governing board that has appointing authority may modify the number, length of terms, and appointing authority of the board of trustees by means of the agreement entered into pursuant to subdivision (c) of Section 101658 or amendment to the agreement, or both, by the county and the governing board that participated in the formation of the authority, if in existence after this formation, and the governing board of any other health care facility that becomes affiliated or merged with the authority, if the following conditions are met: