There is official policy, and there is reality. There is closed, and there is maybe not so closed. People are traveling back and forth on the ferries, out of Grand Case, and out of Juliana. The requirements, and the various carrier’s interpretation of the requirements, appear to be fluid. My advice to the OP is to check directly with St Barth Commuter when you are closer to the date that you want to do a daytrip.
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