Bex Exclusion as per variable selection

Hello SDN experts,

We have a requirement where we need to filter(exclude) by some values (Example GL Account) when user selects previous month or any other historical months but we should include these values when user selectes current month. Is it possible with Bex?

Also, If in the same report it is not possible we can create two , one for current month without exclusion and one with exclusion for historical month selection. But for the historical month we need to show only until previous month for month selection...Can any body suggest how to achieve this?

thanks