Thanks Daniel!
I’m pretty sure I can figure it out, thanks to your hints. It’s just a matter of finding the time! 😉
Thanks Dan, I figured it out, probably about the same time that you posted. I just had to deactivate WP Super Cahce. Interesting how solutions sometimes pop into your head when you walk away from a problem for while.
I’d be interested to know if this is a ‘gotcha’ that catches a few people out.