If that's done with an expression group then I don't think it's possible. I'd use separate expressions and the conditional display option of the expressions to show/hide the required columns as needed. A button or text object could be used to toggle between the two options using a Set Variable action and a variable. If you create a variable vToggle and give it the initial value 0 then the Set Variable action should set the vToggle variable to the value =NOT vToggle. Likewise the conditional display expressions are either =vToggle or =NOT vToggle.