California Code, Government Code - GOV § 31833

For the purpose of this article and Articles 6 and 6.8 of this chapter, age at time of entrance into the retirement system for a person who enters within 90 days, or six months if Section 31840.4 applies, of last rendering service as a member of the Public Employees' Retirement System, another retirement system established under this chapter, the State Teachers' Retirement System, or a retirement system of any other public agency of the state that has established reciprocity with the Public Employees' Retirement System subject to the conditions of Section 31840.2, and who retains his membership in such other system or systems, shall be his age at entry into the first such other system.