I've got a particular scenario in mind and I want to here what people think of it. Let's say that the outbreak of WW2 is delayed long enough for the UK to have another general election, which the Tories win, and in the aftermath the left-wing of Labour Party manages to get Stafford Cripps elected as the party leader (assuming he wasn't expelled for advocating for a popular front). WW2 then breaks out and more or less follows the same path with the allies and soviets crushing fascism. In the post-war elections Labour wins with a landslide. As a result post-war Britain is lead by an even further-left socialist.
How plausible is this scenario, and what implications does this have for post-war British politics and geopolitics. Furthermore, if he was the leader of the Labour Party during the war-time coalition, would he still have been sent as ambassador to the Soviet Union, or sent on his mission to India?