RCW 41.50.165 generally allows you to purchase service credit that you failed to establish or reestablish within the statutory deadline.
Wash. Admin. Code § 415-10-010
Statutory Authority: RCW 41.50.050(5) and 41.50.165. 02-03-120, §415-10-010, filed 1/23/02, effective 3/1/02. Statutory Authority: Chapter 41.50 RCW. 00-22-049, §415-10-010, filed 10/27/00, effective 11/27/00. Statutory Authority: RCW 41.50.050 and 41.50.165. 97-01-014, §415-10-010, filed 12/6/96, effective 1/6/97.