I really enjoyed this one. I was glad to work out the spoonerism and I think my COD (which I think stands for clue of the day or something like that) is 8D. Which I was late getting and made me smile when I did.
I have 4d but wondered if anyone could explain how exactly the penultimate and antepenultimate letters come about. I get the rough gist of where they are from, but not the precise rule that the clue is following.