For reinvestigation, the 180-day period is reckoned from which date when supporting documents are submitted?

• A. From the date of filing of the protest.
• B. From the submission date of supporting documents.
• C. From the date the FDDA is issued.
• D. From the date of receipt of the protest.

Answer: (B)

The 180-day reinvestigation clock starts when the supporting documents are submitted. This is the point at which the case has substantive material for the agency to review, so the period is counted from that date. Starting from the protest filing date, the receipt date, or the FDDA issuance would not reflect the actual review window, since no evidence is yet in hand at those moments. Submitting the supporting documents marks the trigger for the clock to begin and allows the agency to work within the allotted time to complete the reinvestigation.