@Emperor_Taiki:
It has been awhile since i played D-Day but if i remember the allies victory condition is take St. Lo, Cherbourg and Caen within 10 turns
The invasion starts June 6th and operation Goodwood gives the allies solid control of all three of those cities by July 18th.
There are thrity days in june so 30-6=24, 24 +18= 42. 42/10 is 4 and 1/5th.
Each turn in A&A D-Day represents 4 and 1/5th days
This is as good an answer as any.
But…
There is the whole part of the Axis opposing the actual landing of troops by firing on units still at sea for more than one turn and even having pillboxes for more than one turn.
I’m sticking with fluid but also going with the caveat that Taiki has provided the general time frame of the ‘battle.’ i.e. Each turn is maybe more and maybe less than 4-1/5 days but turn 10 is July 18th.