[mlangsdorf]

Stuart Slade's The Big One AH series has one of its primary points of departure that Churchill gets removed in summer 1940. I don't think the mechanism that Slade uses is valid, but a more ambitious Halifax could have pushed harder to be Prime Minister in early May 1940.

Alternately, it Halifax threatened to resign at the end of May 1940 and bring down the Churchill Cabinet, but Churchill managed to keep him on board. A less diplomatic Churchill could have easily provoked Halifax into resigning, and if that caused Churchill to get replaced three weeks into his Prime Ministership, then I could see Germany managing to get a fairly decent treaty terms. Halifax wouldn't have surrendered entirely, but transferring Malta to Italy and Gibraltar to Spain might have been on the table. Halifax could make that deal, expecting to renegotiate after Britain more fully rearmed, and then decide 5 years down the road that Germany had grown in military power faster than Britain. It would just be another decade of appeasement while Germany kept chipping away at the Empire.