A quick side by side of my overhead shot, and SFs, shows that the island is, shall we say, moving.[/size]
Side by side
2021 Update: the island has changed shape again, and the 2 sides of the house have a roof connecting them.
Thank you for posting this TR, it was invaluable in planning the trip.
Is there interest in a 3rd TR for Sandy Cay?
Most of the details have already been laid out by @Something Fishy and OP who have better writing and photography skills than I.