Title says it all. Challenge: Lloyd George becomes the longest-serving PM in the UK.
IOTL, Lloyd George came out of the First World War as an extremely popular figure, not only because he was "The Man who won the War" but also a social reformer before the war. Actually, his reputation peaked in 1918. Bonar Law once thought that he could be a dictator for life if he wanted to. However, he committed various strategic political mistakes before, during and after 1918 that eventually led to his downfall.
Just question how Britain would look like under successive Lloyd George ministries during 1920s and 1930s.