Good question on #1 and I am not sure, but I doubt it. I do believe that you have 24 hours to actually leave when clearing out of the BVI. So I have checked out when I arrived at Great Harbour at 9 AM, then enjoyed the day there and actually left the next morning. Or consider checking out at West End, spend the day/night at Norman, then head to the southside of St. John (Coral Bay, Lamshur, etc.).
Question #2 - you do not need to clear out of the US. Just don't forget to do the SailClear Arrival notice before going back to the BVI.
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