Ed. Code, § 45165

The governing board of any school district not paying the annual or monthly salaries of persons employed by the district in 12 equal monthly payments may withhold, upon election by the individual employee, from each payment made to such employee an amount as follows:

(a) For an employee employed 11 months of a year an amount equal to 8 1/3 percent thereof and the total amount deducted to be paid not later than the 10th day of September next succeeding.

(b) For an employee employed 10 months of a year an amount equal to 16 2/3 percent thereof and the total amount deducted to be paid in two equal monthly installments not later than the 10th day of August and the 10th day of September next succeeding.

(c) For an employee employed nine months a year an amount equal to 25 percent thereof and the total amount deducted to be paid in three equal monthly installments not later than the 10th day of July, the 10th day of August and the 10th day of September next succeeding.

If the provisions of Section 42644 are made applicable to any district the provisions of this section shall apply except that the amount deducted from each regular pay period and ultimate dates for payment of the amount deducted shall be computed and set in accordance with the system adopted under Section 42644.

Once an employee has elected to be brought under the provisions of this section such election shall not be revocable until the commencement of the next ensuing fiscal year. However, in the event any employee leaves the service of the district by death or otherwise before receiving such moneys as may be due him, the amount due him shall be paid within 30 days of the last working day to him or any other person entitled thereto by law.

This section shall apply to districts that have adopted the merit system in the same manner and effect as if it were a part of Article 6 (commencing with Section 45240) of this chapter.