If you want to force the user to select Department dimension value but not CostCenter value and vice versa, can be done like this

But what if we let user chooses Department in a range between 1000..9999, then the user can choose any CostCenter
or
if the user chooses a Cost center <=999, then the user can choose any Department value
I have tried using advanced rules with an additional condition for CC<=999 then Department *
Any ideas?