Section 831.1753 - Civilian and military service of an individual affected by an erroneous retirement coverage determination(a) For the purpose of crediting service for which actuarial reduction of annuity is permitted under § 831.303(d) for an employee who enters phased retirement, the deposit amounts under § 831.303(d) form the basis, along with the phased retiree's age, for any actuarial reduction of the phased retirement annuity for such unpaid deposits.(b) No deposit payment for service described under § 831.303(d) may be made by the phased retiree when entering full retirement status.(c) As provided under § 831.1741(b) , the amount of any deposit under § 831.303(d) at the commencing date of the individual's phased retirement annuity, or unpaid balance thereof, including interest computed to the effective date of phased retirement annuity, will be the basis, along with the phased retiree's age, for any actuarial reduction of the phased retirement annuity for such unpaid deposit.(d) As provided under § 831.1742(d)(1) , any actuarial reduction for any unpaid deposit service under § 831.303(d) applied to the phased retirement annuity, as described in § 831.1741(b) , is increased by cost-of-living adjustments and applied to the monthly installment derived from the composite retirement annuity.