flyingbird
Ask them both about their courses. The GCNS course was set up orignally to the ICAO 7192 D3 syllabus in 2002 so I can't imagin they would have moved away from that, particularly as that is the basis for all European ops training.
I would also speak with Bristol GS (Mr, Alex Wittingham, if my memory serves me) or send them an email and ask whether or not they are running the course or planning to. I know there was interest on their part some time back. As I write this the other possibility that comes to mind is in Dublin at Bolton Street, I forget the college's actual name, but they used to also run a course. Maybe someone else on the forum can help with that.
Whatever you choose, good luck with it.