The particular aircraft you are talking about was the forth of five that were produced, it originally had the intake pictured here on the prototype VX784, the intakes were located in the wing roots after the first aircraft when turbulence from the cockpit canopy caused interrupted intake airflow. Being the forth aircraft I'd assume the NACA intake was an experimental assessment to see if the dorsal intake could be made to work with the canopy turbulent flow, the raised lip around the intake is obviously an airflow management tool, but what the aim of it is is anybodies guess, we need an aerodynamics specialist.
https://www.baesystems.com/en/heritage/avro-707