I don't like BB either but I am not familiar with the 30 kt provision you mention. What companies have this in their contract? The Moorings does not.
My charter was through Navigare, and they have a 30 kt limit in the charter agreement. I do realize that the balls usually have a 40 kt limit, so I guess the idea would be that we would return to Road Town if the forecast was more than 40 kts.