Bogus’ has only set twice before, the last time in 2017. The central theme idea then was very similar to today’s, it’s 27,321 if you want to look it up (spoiler alert unless you’ve done today’s). Prior to that Bogus set a puzzle in 2016 (number 26,046) which again has the same central idea. It was revealed at the time that ‘Bogus’ was a collaboration between three regular Guardian setters, Puck, Arachne and Nutmeg. I suspect the same or similar today. ‘Pink organ’ has definitely been used more than once before by yesterday’s setter which might be a clue ;-)