5 CFR §536.102

1. (a)Subject to the exclusions in paragraphs (b) through (e) of this section, this part covers any employee who, at the time this part is applied—
   1. (1)Is in a covered pay system; or
   2. (2)Is moving to a position under a covered pay system from a position not under a covered pay system, as long as the individual was an employee as defined in 5 CFR 536.103 while serving in the position in a noncovered pay system.
2. (b)An agency may not provide grade or pay retention under this part to an employee who—
   1. (1)Is reduced in grade or pay for personal cause or at the employee's request;
   2. (2)Was employed on a temporary or term basis immediately before the action causing the reduction in grade or pay;
   3. (3)Does not satisfactorily complete the probationary period prescribed by 5 U.S.C. 3321(a)(2), and, as a result, is removed from a supervisory or managerial position;
   4. (4)Is entitled to receive a saved rate of basic pay under 5 U.S.C. 3594(c) and 5 CFR 359.705 because of removal from the Senior Executive Service and placement in a civil service position (other than a Senior Executive Service position) under 5 U.S.C. 3594(b)(2);
   5. (5)Moves from an Executive Schedule position paid under 5 U.S.C. chapter 53, subchapter II, or a position whose rate of pay is fixed by law at a rate equal to a rate for the Executive Schedule;
   6. (6)Moves between positions not under a covered pay system or from a position under a covered pay system to a position not under a covered pay system;
   7. (7)Moves to a nonappropriated fund position as described in 5 U.S.C. 2105(c) (except a position occupied by a prevailing rate employee);
   8. (8)Moves from a nonappropriated fund position as described in 5 U.S.C. 2105(c) (except a position occupied by a prevailing rate employee) to a position in a covered pay system, unless covered by § 536.302(a); or
   9. (9)Is reduced in pay upon termination of a critical position pay authority under 5 CFR part 535.
3. (c)An agency may not provide grade or pay retention under this part based on the grade or rate of basic pay held by the employee during a temporary promotion or temporary reassignment. However, a temporary promotion or temporary reassignment does not affect an employee's preexisting entitlement to grade or pay retention.
4. (d)An agency may not provide grade retention under subpart B of this part to an employee who moves from a position not under a covered pay system to a position under a covered pay system.
5. (e)An employee loses eligibility for or entitlement to grade or pay retention under the conditions specified in §§ 536.207, 536.208, and 536.308.