Any and all payments due to a deceased retiree or deceased annuitant that have not been made, or that have been made but are non-negotiable after the retiree's or annuitant's death, including, but not limited to, final annuity payments and partial lump-sum distributions, may be made payable to the designated beneficiary or beneficiaries on file with the system on the date of the retiree's or annuitant's death.