(a) For each determination to pay a recruitment incentive under this subpart, an agency must document in writing—

(1) The basis for determining that a position is likely to be difficult to fill, as determined under § 575.106;

(2) The basis for authorizing a recruitment incentive; and

(3) The basis for the amount and timing of the approved recruitment incentive payment and the length of the required service period.

(b) An agency must make the determination to pay a recruitment incentive before the prospective employee enters on duty in the position for which recruited.