I have almost definitely decided it will be Saturday. (Malton is closed on a Sunday, apart from anything else).
We haven't agreed a start time. I was going to suggest a little earlier than last time, so that we get to Malton while the market is still going, and so that we have time for a civilised morning tea stop at Castle Howard.
With apologies to Solty, how about starting at maybe 9 or 9.30? (Maybe Arch will give you breakfast while you wait if you ask nicely, Solty...) Same place, at the west end of the Minster. The Monk's Cross or Grimston Bar Park and Rides would be the ones to go for if you're driving to York.