BBB. “Before breaking bulk”, that is, before commencing discharge or opening of the ship’s hatches.
This indicates a time for some formality to take place, e.g., for the payment of freight, before cargo discharge commences. Customarily freight was payable on delivery at the destination and this term made even more; certain that the shipowner was to receive payment before the cargo was discharged. Now, advance freight is common and the BBB term is falling into disuse.