What were the initial objectives of battle of France?

Question

And how much the original plan differ to the one put forth by Manstein?

Answer 1

1. to sucker the BEF and best French divisions into the Low Countries.

2. to breakthrough at Sedan and reach the Coast, thus bagging the allied divisions suckered into the trap.

Those were the initial objectives.

Answer 2

The objectives of "Case Yellow" or Fall Gelb, or Operation Sickle Cut, pulled forth again by Manstein, was to try and force the allies into an early white peace, and has it's roots in the Schlieffen Plan of the first world war. The allies expected an assault on Belgium to avoid the French defensive lines, and an assault on Belgium would draw them from their trenchs on the French Border and into the field. Then the Panzers would slash in and cut both the BEF and the French forces off from the rear. Enveloping them, and crushing them. What was not predicted was the success of the movement, and the utter devastation of Allied forces.