3. Employee who has previously ceased contributions. An employee who has previously withdrawn from elected to cease contributions to the retirement system, whether or not accumulated contributions have been withdrawn, may choose to rejoin the system within 3 years of withdrawal at any time under the following conditions.

A. The If the employee withdrew accumulated contributions and is rejoining the system within 3 years of the date that a refund was paid under section 18306, the employee must repay to the retirement system an amount equivalent to the withdrawn accumulated contributions plus the amount of interest which that would be required of any terminated employee who had become reemployed and had elected to rejoin the retirement system and to repay the contributions.

A-1.__If the employee withdrew accumulated contributions and is rejoining the system more than 3 years from the date that a refund was paid under section 18306, the employee may not repay to the retirement system the contributions withdrawn under subsection 2.

B. The employer must still be a participating local district allowing new membership in the retirement system.

4. Employee who has previously withdrawn rejoins after 3 years. An employee who has previously withdrawn from the retirement system may choose to rejoin the system after 3 years of withdrawal under the following conditions.

A. The employee may not repay to the retirement system the contributions withdrawn under subsection 2.

B. The employer must still be a participating local district allowing new membership in the retirement system.

5. Limit on right to rejoin. The right of an employee to rejoin under either subsection 3 or 4 is limited to one occurrence.

6. Restoration to service. If any person who is the recipient of a service retirement benefit is covered by the United States Social Security Act upon being restored to service, continuation of that person's benefit is governed by the following.