Thanks to one and all, i'm still baffled. The fact that the NOT was in capital letters, suggested it wasn' Ethelred the unready, unless i am reading toomuch into it.
I googled "Which king liked to be punctual?" and got that answer.Not really sure that it 's the answer to the clue-I've checked lists galore and had given up.
I posted that answer of King Louis XVIII a while back, not doing the quiz and knowing the requirements but someone came back and said it was Kings and Queens of England.