How to: limit invoice selection with cut-off date based on due date

We are implementing staged dunning letter functionality with advanced collections. Currently, the dunning letters are sent manually. The requirement is that advance collections should only select delinquency after a specific due date (which will be the go-live date). 

The business justification behind is that if we don't set a cut-off date the customer will receive a first dunning letter for an invoice for which we have already sent a second or third letter manually.