In addition to the benefit limitations specified in this part, if a member participates in other defined benefit plans maintained by the employer, to the extent the aggregation of benefits payable under those plans and pursuant to Part 3 (commencing with Section 20000) are subject to and exceed the limits prescribed by Section 415 of Title 26 of the United States Code, the benefits payable pursuant to the other defined benefit plans maintained by the employer shall be reduced, but not below zero, to the extent necessary to satisfy Section 415, before adjustments to the benefits provided under Part 3 are made. Nothing in this section shall limit a member’s entitlement to replacement benefits as provided by Section 21757.