I understand the point you're trying to make.
We did not possess God's grace while we were yet sinners. It was made available to us while we were yet sinners. And that grace, that was made available to us while we were yet sinners, is only given to those who respond in faith to the offer of that grace. Faith is the conduit through which God's grace flows.
"Jesus Christ, 2through whom we have gained access by faith into this grace in which we now stand. " - Romans 5:
"5who through faith are shielded by God’s power until the coming of the salvation that is ready to be revealed in the last time. " - 1 Peter 1:5
No faith means no conduit through which to receive God's grace. That's why we have to believe, and keep on believing, in order to be in the grace of God. Freegrace says you still have God's grace in salvation even if you no longer have the conduit of faith by which you receive God's grace in salvation.