On May 25, 2021, US Customs and Border Protection (CBP) published in the Federal Register a document [Docket No. USCBP–2021–0009; CBP Dec. 21–04] that reopens the comment period for the interim final rule published on March 15, 2021 which amends the CBP regulations to provide for mandatory advance electronic data (AED) for international mail shipments. Although the comment period for this IFR closed on May 14, 2021, CBP has decided to reopen the comment period for an additional 30 days. The interim final rule published on March 15, 2021 (86 FR 14245), was effective March 15, 2021. Comments must be received on or before June 24, 2021.