Thanks mate! I called customer services and they told me I AM entitled to a courtesy car! They also gave me the service manager's name at Derby BMW Stratstone. After a brief conversation with him he told me he will call back in 10 minutes. 4 hours later I got a call from the service representative who originally booked my car in and he said the new light control module has arrived! That's a little strange isn't it? On Friday it was going to be Wednesday at the earliest but as soon as I call in demanding a courtesy car the part magically arrives from Germany! I've been told I will be called tomorrow morning with an update.
I'm still furious, I've been almost 2 weeks without a car!!! I've been thinking of ways to reduce the bill to compensate for this. Perhaps get them to remove some of the labour charge.