Fernando,
You have confused me here (I am easily confused though).
Is there a suggestion that Gulf Air (GF) is interested in BRS or CWL?
Thus far the only rumour is I am aware of is Emirates (EK) from CWL.
terrier,
I note your remarks about the runway extension and I agree with you that at present it is in the too-hard-to-do-basket and is unlikely even to be contemplated for at least a decade and then, as you suggest, it might not be necessary anyway.
However, I hadn't realised there was a problem with the terrain to the east from a physical point of view - the land seems flat although the A 38 would have to be covered. NIMBY-wise certainly there would be a problem because it would mean encroaching on the common land.