(a) An investment manager other than a bank having a contract with a public retirement system under Section 802.204 may not be a custodian of any assets of the reserve fund of the system.
(b) When demands of the public retirement system require, the governing body shall withdraw from a custodian of system funds money for use in paying benefits to members and other beneficiaries of the system and for other uses authorized by this subchapter and approved by the governing body.