(d) Authority to request supplemental information. Whenever the PBGC has reason to believe that any of the requirements of
§§ 4041.21 through 4041.24 of this part were not complied with, or in any proposed termination that will result in a reversion of residual assets to the contributing sponsor, the PBGC may require the submission of information supplementing that furnished pursuant to
§ 4041.24. A request for additional information under this paragraph shall be in writing and shall suspend the running of the 60-day (or extended) review period described in
paragraph (a) of this section. That period shall begin running again on the day following the filing of the required information. If a plan administrator or contributing sponsor fails to submit information required under this paragraph within the period specified in the PBGC's request, the PBGC may issue a notice of noncompliance in accordance with
§ 4041.26 or take other appropriate action to enforce the requirements of title IV of ERISA.