My thoughts are:
Having the advance to the channel would have been a bad thing for Germany or the Soviets IMO because they both wanted to attack each other, preferably when Britain was out of the way and the other nation was war-weary.
I think for the Soviets, Barbarossa would come even sooner and Stalin would be even less prepared. Also, the Germans could cut into the centre of the Russian advance, isolating ands maybe destroying those in Europe?
For the Germans, well the Soviets in France could open another front - much like D-Day.
I expect that when both sides got near Spain, that memory of the Civil War there might start tensions?
Would the BoB have happened? Would Britain just sue for peace? What would I-16's add, if anything? Would Hitler be more, or less patient about Barbarossa? Would the US realise it's error, crap it's pants and attack?
I like someone's ideas of attacking Germany from the West, halting the German and maybe Soviet advance into Poland, nipping it inthe bud. What would've been the consequences of that though?