If a designated beneficiary who is receiving payments for life dies on or before the 15th day of a month, the Board of Trustees may not pay any portion of the designated beneficiary’s allowance to the designated beneficiary’s estate for the month in which the death occurs. If a designated beneficiary who is receiving payments for life dies on or after the 16th day of a month, the Board of Trustees shall pay to the designated beneficiary’s estate the entire allowance due to the designated beneficiary for the month in which the death occurs. If a retiree dies on or before the 15th day of a month, the Board of Trustees may not pay any portion of the retiree’s allowance to the designated beneficiary or the retiree’s estate for the month in which the death occurs. If a retiree dies on or after the 16th day of a month, the Board of Trustees shall pay the entire allowance due to the retiree for the month in which the death occurs: to the designated beneficiary; or if there is no designated beneficiary, to the retiree’s estate.