Length of Service With FPI
After 18 months of service and payable in the 19th month
After 30 months of service and payable in the 31st month
After 42 months of service and payable in the 43rd month
After 60 months of service and payable in the 61st month
After 84 months of service (& more) and payable in the 85th month
Longevity pay allowances shall be added after the wages for each actual hour in pay status have been properly computed.
28 C.F.R. § 345.55