I think that’s a pretty desperate attempt by the right wing press to get one over him - and I speak as a sometime fan of the right wing press
Saying something is lodged in your mind because people have been talking to you about it isn’t anything like announcing a policy whilst in full possession of the facts (seeing as you’re the sitting PM), and then having to un-announce it because you thought you could just ignore the facts right until they came and slapped you in the face. This is what Starmer did time and time again.