Several years ago we took a captain on day one of our charter in St. Vincent and the Grenadines just so we could get out of the marina at 8AM vs. noon. The bonus was, we got some of the best advice i have ever gotten regarding some "secret" anchorages etc. from the captain. Even though you may have been to the BVI umpteen times, I'll bet you can garner just one piece of information that will offset the 10% bad feeling you have about getting "duped" by the change in plans. Besides, most decisions in life are not as easy as 90/10 are they?