The PBGC applies the rules in subpart D of part 4000 of this chapter to compute any time period under this part. However, for purposes of determining the amount of a late payment interest charge under Sec. 4007.7 or of a late payment penalty charge under Sec. 4007.8, the rule in Sec. 4000.43(a) of this chapter governing periods ending on weekends or Federal holidays does not apply. [68 FR 61352, Oct. 28, 2003]