Phil,
it is from the first batch of NQLRT. At Nottingham there was a HeliJohn version on the traders stand in front of us. Something about it felt wrong to the three of us in the weekend long conversation, bit we couldn't mail what it is!. It could be that familiarity has made us see the NQ one as being representative. The 31, on the other hand, is spot on.
Must add the hand rail to the post show list of jobs!
Simon