No I've just realised I did last week's puzzle! But it was the puzzle served to me by going to observer.co.uk/everyman as I usually do (though did not do last week, hence not recognising the crossword as an old one).
Ah, well, I get to do two Everymans (Everymen?) this morning.
Perhaps this needs to be fixed? (Though it's easy enough to find the correct puzzle via the menu.)