I got a reply, offering me a choice of two times on the Thursday afternoon, at an address in Amsterdam Buitenveldert.
I'm not quite sure what they are thinking: how many people have the time and opportunity to take a weekday afternoon off to travel to somewhere in Amsterdam at their own expense to give KLM 45 minute of their time? A couple of pensioners living just around the corner, perhaps?
I really would like to be able to participate, but I'm in the Netherlands for the day only, and have other commitments.
Johan