Nanny Cay is definitely a good bet. We had the unenjoyable task of circling on front of it this morning on a 41' mono with a PC hovering over stern also waiting to fuel. We arrived at exactly 8am but there were a few ahead of us and some fuel dock slips seem to be permanently occupied by large crewed cats who are not refueling... At least it appeared that way this past week. Regardless once tied up we were easy in and out.