Sadly, because the war started this early both Britain and France had to commit every division on the mainland to hold the Italian, German and Belgium fronts. Which meant that my mobile respons army that sat right behind the maginot - in anticipation for the eventual breakthrough - had to move to Belgium to prevent that front from collapsing. Which meant I had little to nothing to push back the Jerries and defeat was inevitable.
Most of the british and french troops did manage to evacuate, though.
I still blame the whole debacle on those filthy commies.