Haw. Rev. Stat. § 88-343: Return to service of a former member who has vested benefit status.

If a former class H member who has a vested benefit status as provided in section 88-341(b) returns to service before the former member's retirement, the former member shall again become a member and shall contribute for membership service as provided by the law in effect during the member's reenrolled period of membership, and the former member shall be credited with service credit for the service the member had when the member terminated employment and the member's new and previous accumulated contributions shall be combined.