Don't bother.

4 weeks in May/June. Never had an issue finding a FCFS. At this end of the season its not an issue and as soon as BEYC and Saba come back next season I suspect BB will stop being an issue or something of use to anybody, ever...and (we can only hope) will disappear.

Most nights all the BB/Children's balls were taken but there were First Come First Serve Balls open all night. That includes Cooper on two occasions where FCFS were open all night.

Cooper seems to be the main issue at the moment...everywhere else plenty of balls and plenty of anchoring options. My advice would be don't bother with BB, but if you want to be safe, don't aim to arrive late in the day to Cooper.

Norman - all FCFS in June and plenty of them!
Marina Cay / Trellis - all FCFS and plenty of them and good anchoring anyway at MC.
North sound - Anchor off Sand Box! Save some bucks! It's a beautiful spot, great holding and easy RIB to Leverick. Or otherwise FCFS Leverick.
Anegada - plenty of FCFS and great backup of anchor at Pomato Point, great holding, beautiful spot and Fab restaurant on the Beach (Sid's Place).
JVD - Diamond Cay - FCFS, Great harbour FCFS. All good. No need for BB

All this info accurate as at end June this year. I'm sure others will correct me if things have changed.

Oh...and have an amazing time!!! Cant see anything horrible brewing in the Atlantic as at today's most recent satellite pics so hopefully you will have awesome weather for the duration too! Enjoy!