I think 10 minimum will be a cinch, but I believe it shouldn't be exclusive to just armor. We need other armed forces 'vehicles' involved to help out with enlistment. Like aircraft, boats, soft skins. And it should allow RTR's to be a part as well. Like the WSN T34 and M16 as well as the Trumpeter T34's and their M16 kit.
Heng Long tanks, Tamiya tanks, Trumpeter tanks ... they might take some time so at least a year?
Radio Control or static to even scratch built items in WWII or any battle in recorded history, it could be a massive military movement ever seen here!

~ Jeff