B. An employee of the participating local district who is a member under the retirement system on the date on which the employer provides a plan under section 18252-B may elect to remain a member under the retirement system or to become covered under a plan provided by the employer under section 18252-B.

(1) If the employee elects not to remain a member, the election is effective as of the first day of the month in which no contributions or pick-up contributions are made to the retirement system by the employee. An employee who elects not to remain a member shall may, at the employee's discretion, withdraw accumulated contributions in accordance with applicable requirements of law and rule and retirement system procedures.

(2) An employee who elects not to remain a member under the retirement system may later elect to again become a member.

(a) Membership service credit for an employee who elects to again become a member under the retirement system under this subparagraph begins as of the effective date of the first contributions or pick-up contributions to the retirement system following the employee's election under this subparagraph.

(b) An employee who rejoins the retirement system under this subparagraph may not pay contributions or pick-up contributions or receive service credit for the period during which the employee elected not to be a member under the retirement system. The employee may, in accordance with section 18304, repay contributions refunded under subparagraph (1), unless to so elect would have the effect of requiring the employer, without the employer's agreement, to make an employer contribution to both the retirement system and the plan provided by the employer under section 18252-B.