context: Governor Vaudreuil, who harboured ambitions to become the French commander in chief (in addition to his role as governor), acted during the winter of 1756 before those reinforcements arrived. Scouts had reported the weakness of the British supply chain, so he ordered an attack against the forts Shirley had erected at the Oneida Carry. In the March Battle of Fort Bull, French forces destroyed the fort and large quantities of supplies, including 45,000 pounds of gunpowder. They set back any British hopes for campaigns on Lake Ontario, and endangered the Oswego garrison, already short on supplies. French forces in the Ohio valley also continued to intrigue with Indians throughout the area, encouraging them to raid frontier settlements. This led to ongoing alarms along the western frontiers, with streams of refugees returning east to get away from the action.
question: Where was there a strength in British supply chain?