When Great Harbor moorings are full we anchor for free in 30'-40' of water. Better neighbors and less noise.
Coming from Anegada I'd shoot for Diamond Cay if it has room. Its a delightful overnight spot with lots of critters. Like Kirk, we love spending time around Jost and hit all three anchorages in January. If you want to do a day on White Bay you can pop over from Diamond Cay in the morning.
Cheers, RickG