More patrols and earlier convoy air cover

A one-in-three readiness rule still yields roughly ten extra French submarines on patrol, increasing sightings, intelligence reports, and interception opportunities around northern exits. French sloops and Caribbean bases add escort capacity and extend the supporting network for the Atlantic campaign. Béarn's Swordfish could protect critical convoys and demonstrate the escort-carrier concept earlier than it developed historically. Her six-inch battery also makes a surfaced U-boat attack through the middle of a convoy exceptionally dangerous, even before aircraft locate the submarine.