5 C.F.R. § 330.610

(a) CTAP eligibility begins on the date the employee meets the definition of surplus or displaced in § 330.602.

(b) CTAP eligibility ends on the date the employee:

(1) Separates from the agency either voluntarily or involuntarily;

(2) Receives a notice rescinding, canceling, or modifying the notice which established CTAP eligibility so that the employee no longer meets the definition of surplus or displaced;

(3) Is placed in another position within the agency at any grade or pay level, either permanent or time-limited, before the agency separates the employee; or

(4) Is appointed to a career, career-conditional, or excepted appointment without time limit in any agency at any grade or pay level.