Loading; in another forum someone removed breakthrough from the 3 Moorside Edge transmitters which were all of 1 mile from him !
Suggest :=
1) mainly for overhead lines use RF3 ( included in I Plate)
2) for pickup on 'phone extensions, use filtered faceplate ( NOT I plate) to stop 'phone extensions acting as aerial.
3) If these are not a 100% cure, consider filtering/spacing from 50Hz wiring.