Apologies if this has been done before.

I have just booked a flight plus car for around 15% less than the cost of flight only. Another BA IT quirk, or something else? In the past, I have had a car for a quid and a weekend in an S-Class Merc for under £100, but this is the first time I have, effectively, been paid to take a car!

Not shouting about the details, for obvious reasons.