Just an update.
They managed to look into the problem yesterday and and with bumper/headlight etc off it was going to be no good me taking the car as they were still trying to fault find. Anyway got a call this lunch time to say the fault is apparently a lighting control module but the part is on "back order" so expect it in 5-10 working days! Car off the road till then!
Dealer has contacted BMW to organise a courtesy car in the meantime, just waiting for BMW to phone to arrange it....I hope its an M3, M5, M6 etc....lol, probably be a 116i but at least its transport.