Larry,
Records show that Spitfire X4561 (
www.spitfire.ukf.net) was delivered to 92 Sqn in December 1940 as QJ-B. I have also found numerous Photographs depicting 92 Sqn Spitfires showing letters QJ as late as December 1941 on the Imperial War Museum website (
www.iwmcollections.org.uk). Hope it helps.
Regards,
Paul.