No person receiving a disability pension under the provisions of Sections 4.20.140 or 4.20.150 shall become a nonresident of the state of California without permission of the board; provided, however, that the provisions of this section shall not apply to any person whose age and aggregate service, including the time during which they have received said disability pension, are such as would entitle them to service retirement benefits if they were not receiving a disability pension. (Ord. 3549-NS (part), 1957: Ord. 2188-NS § 17, 1938)