Right, that's it, I've had enough. I'm out of here. I have canceled the remaining 3 rentals, and made other arrangements for those periods (such as taking a Scottish CityLink bus at one point!~)
Needless to say, the 3rd rental posted as above, with no bonus. So I really can't be bothered any more with this rubbish. Was there no feedback from Flying Blue, if this thread was sent to them? It really is false advertising, this promotion, and something should be done about it.
I am happy for those for whom it all worked out ok, like mine did last year, hope you get to the end with no further nonsense.