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Additionally, ROTOR re-arranged the existing RAF Fighter Command structure into six " Sector Operational Commands " ( SOC ) with their own command bunkers ( three level ' R4 ' protected accommodation ).

Only four of these were built.

Additional " Anti-Aircraft Operations Rooms " were built to coordinate the British Army's AA defences in the same overall system.

The entire network of bunkers, radars, fighter control and command centres used up 350, 000 tons of concrete, 20, 000 tons of steel and thousands of miles of telephone and telex connections.