A carrier will only issue a switch BL once the first set of originals is surrendered, and the change has to stay truthful about the cargo and the carriage. Mishandled, it carries real fraud and liability exposure, so the forwarder coordinates the request tightly with the carrier and the parties rather than treating it as a routine reissue.
Glossary
Switch Bill of Lading
A second set of original bills of lading issued to replace the first set, used to change details such as shipper, consignee, or port marks. It is common in back-to-back or triangular trades where the end buyer should not see the original supplier.