Quick update:
Cleaning the plug and socket didn't work, it looks like there is damage on the BCM board. Thankfully there is a Jag specialist with an electronics Wizz nearby so I'm going to whip the bcm out over the weekend and take it down there. They said it should be plug and play once they've re-pinned it but they want me to bring the car down after so they can re-pin the plug as well.
I should know in about a week if it's worked or not.
If not I'm guessing I'll have to fork out for a new bcm and programming from JLR main dealer.
Alex