I try to be more clear.
Actually i say right the opposite.
Let’ say it like this : the american makes an amphibious landing in a beach region with japanase defender in the adjoining region so has to fight the japanese :
In both cases there are not any units on the beachead at he end of the combat.
Is it right ?
If it is how is it possible to have units in there ?
Am i missing something in the rules?