No law requires registered in UK if based here. Therefore no Airlines/Charters. (exept Atlas, and short/medium/long term flagging out in summer/Autumn/Winter and Spring!) Lots of private stuff though. Try any london based GA airfield plus companies which provide crews for a/c owners. Some in Luton definately try also BIG/STN/MCT/LBA and JSY if you can get residency also MAN.