https://www.gao.gov/products/441638

B-188242: Aug 9, 1977

WAS GRANTED. THE GOVERNMENT'S OBLIGATION THEREUNDER HAS BEEN DISCHARGED AND NEITHER EMPLOYEE'S VESTED RIGHT NOR GOVERNMENT'S OBLIGATION IS SUBJECT TO CHANGE UNLESS LAW OR REGULATION HAVING FORCE AND EFFECT OF LAW EXPRESSLY PROVIDES THEREFOR. MOSES - SUBSTITUTION OF LEAVE WITHOUT PAY FOR ANNUAL LEAVE: THIS ACTION IS IN RESPONSE TO THE APPEAL OF MR. MOSES WAS HIRED BY NASA AS A REEMPLOYED ANNUITANT...

https://www.gao.gov/products/103182

B-188242: Aug 9, 1977

A former temporary federal employee appealed a settlement which disallowed his claim for substitution of leave without pay for 123 hours of annual leave used by him while employed. The request for retroactive conversion may not be granted after the employee properly requested, was granted, and used the annual leave...