If such a couple has reconciled to the extent that they desire to have marital relations with each other, then they no longer have just cause to remain legally separated (which is what civil divorce accomplishes in the eyes of the Church) and ought to fully reconcile and repair their marriage. They cannot claim simultaneously that there exists substantial reason for them to remain separated while still indulging in an act reserved to couple married in the eyes of God and society. And, when that substantial reason to live separate lives no longer exists, the Church expects them to reconcile.
