Reading back through Mays 'Strange Victory' there are a couple remarks that describe the plan in place as a attack through Belgium, with the main effort on the Belgian plain - north of the Meuse River. Also the armored Corps were distributed to seperate armies and not concentrated.
Now these remarks dont indicate the Germans were locked into such a plan for September, or whenever they attacked. When Halder was able to turn his attention to the west after the Polish campaign he was even then disatisfied with the plan & directed the development of alternatives to be tested in early November wargames. Since the Germans exhaustively tested their plans in map and field exercises we must assume Halders doubts derived from the plan failing these tests. Were the priority France vs Poland we have to consider that the campaign concept of Plan Yellow might be better developed. But, OTL it took 6-7 months to develop the sophisticated Sickle Cut plan as we know it. Contrary to Mainsteins fans it did not spring whole from his genius in Nov 39, but was evolved through a series of staff studies. field tests and wargames spanning October 39 through March 1940.
So, what we might see from the Germans in a September 1939 campaign is the main effort concentrated north of the Meuse River, the armored corps may or may not be concentrated, and the Netherlands may be left alone. Making the main effort south of the Meuse River was complex & required a lot of extra staff planning & field testing to work out. Even after all that in May 1940 many German leaders thought it would fail. So its unlikely it would be attempted in 1939.
Now these remarks dont indicate the Germans were locked into such a plan for September, or whenever they attacked. When Halder was able to turn his attention to the west after the Polish campaign he was even then disatisfied with the plan & directed the development of alternatives to be tested in early November wargames. Since the Germans exhaustively tested their plans in map and field exercises we must assume Halders doubts derived from the plan failing these tests. Were the priority France vs Poland we have to consider that the campaign concept of Plan Yellow might be better developed. But, OTL it took 6-7 months to develop the sophisticated Sickle Cut plan as we know it. Contrary to Mainsteins fans it did not spring whole from his genius in Nov 39, but was evolved through a series of staff studies. field tests and wargames spanning October 39 through March 1940.
So, what we might see from the Germans in a September 1939 campaign is the main effort concentrated north of the Meuse River, the armored corps may or may not be concentrated, and the Netherlands may be left alone. Making the main effort south of the Meuse River was complex & required a lot of extra staff planning & field testing to work out. Even after all that in May 1940 many German leaders thought it would fail. So its unlikely it would be attempted in 1939.