Mellotronists

There have been many subjects debated here since I joined the list. However, I haven't yet seen one about who holds the title of having played on the earliest session.
Anyone out there know who on the list has played on the earliest commercially available recording.
Home sessions, demos and wasting time in music shops don't count, sorry Martin!
Come to think of it, I'm wondering whether anyone would own up to it anyway!
Come on, lets find out who really is the Golden Oldie among us!
Andy K
m400 #1405