CSMS #45035166 - Generalized System of Preferences Updates U.S. Customs and Border Protection sent this bulletin at 12/01/2020 04:53 PM EST Cargo Systems Messaging Service CSMS #45035166 - Generalized System of Preferences Updates The Generalized System of Preferences (GSP) changes effective December 30, 2020 have been updated in ACS CERT, ACE CERT and ACS PROD. Questions or concerns should be directed to Entry Summary, Accounts & Revenue Division (ESAR) at esar@cbp.dhs.gov.