Thanks for your enquiry. I've taken the liberty of removing your other post as it was a duplicate of this, to prevent replies to the one enquiry ending up in two different places.
During the period of the Second World War, Vosper and Thornycroft were two separate companies, both manufacturing motor torpedo boats, with Vosper the more significant of the two, and they only merged to become Vosper Thornycroft in 1966.
I've not managed to find any record of a Leonard Lincoln on the Unit Histories web site's lists of Royal Navy, Royal Naval Reserve, and Royal Naval Volunteer Reserve Officers
, nor in any of the Navy Lists I have, though I don't have them all by any means, as there were several lists produced for each year throughout the war years. He's not in our awards database, nor in the old membership list for the Coastal Forces Veterans Association either, so no leads I'm afraid.