(4) Supplemental responses. If, at any time after the later of the receipt of a request under
paragraph (a) of this section, or the filing of PBGC Form 600, the plan administrator submits additional information to PBGC with respect to the plan termination under
section 4041(c)(2) of ERISA and
§ 4041.45, the plan administrator must, not later than the 15th business day (as defined in
§ 4000.22 of this chapter) after each additional submission, provide the additional information to any affected party that has made a request under
paragraph (a) of this section.