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 Employee who has previously withdrawn rejoins after 3 years. An employee who has previously withdrawn from the retirement system may choose to rejoin the system after 3 years of withdrawal under the following conditions.

A. The employee may not repay to the retirement system the contributions withdrawn under subsection 2.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

A. The person may elect to have the service retirement benefit continued during the period of time the person is restored to service and the person may not accumulate any additional service credits.

B. The person may elect to have the service retirement benefit terminated, again become a member of the retirement system and begin contributing at the current rate.

(1) The person is entitled to accumulate additional service credits during the period of time the person is restored to service.

(2) When the person again retires, the person is entitled to receive benefits computed on the person's entire creditable service and in accordance with the law in effect at the time.

C. Upon being restored to service, the person shall must elect to have benefits either continued or terminated. If written notification of the person's election is not received by the executive director within 60 days of restoration to service, the person is deemed to have elected