CA Gov't Code Section 19142

(a)

Every person accepts and holds a position in the state civil service subject to mandatory reinstatement of another person.

(b)

Upon reinstatement of a person any necessary separations are effected under the provisions of Section 19997.3 governing layoff and demotion except that (1) an employee who is not to be separated from state service need not receive advance notification as provided in Section 19997.13, and (2) seniority may not be counted as provided in Section 19997.3 when this would result in the layoff of the person who has the reinstatement right. Under that circumstance, qualifying service in classes at substantially the same or higher salary level is the only state service that may be counted for purposes of determining who is to be separated.