5 CFR § 550.132 - Relation to overtime, night, and Sunday pay.
(a) Premium pay for holiday work is in addition to overtime pay or night pay differential, or premium pay for Sunday work payable under this subpart and is not included in the rate of basic pay used to compute the overtime pay or night pay differential or premium pay for Sunday work.
(b) Notwithstanding premium pay for holiday work, the number of hours of holiday work are included in determining for overtime pay purposes the total number of hours of work performed in the administrative workweek in which the holiday occurs.
(c) The number of regularly scheduled hours of duty on a holiday that fall within an employee's basic workweek on which the employee is excused from duty are part of the basic workweek for overtime pay computation purposes.
(d) For a Border Patrol agent covered by 5 U.S.C. 5550 and subpart P of this part, no holiday premium pay is payable for regularly scheduled overtime hours within the agent's regular tour of duty, as required by 5 U.S.C. 5550(b)(2)(C), (b)(3)(C), and (c)(1)(A). The overtime supplement payable for such scheduled overtime hours is not part of the agent's rate of basic pay used in computing the holiday premium pay for other hours that qualify for such premium pay.