R. Scott Clark has given an exposition on the ninth point of Synod Schereville, which states:
Therefore Synod rejects the errors of those:
9. who teach that there is a separate and final justification grounded partly upon righteousness or sanctity inherent in the Christian (HC 52; BC 37).
[HC: Heidelberg Catechism; BC: Belgic Confession]
The audio file of this exposition can be found here. The teaching of the existance of "final justification" is indeed error. "Final justification" is a legal fiction which does not exist, contra the heresies of the New Perspective and the Federal Vision, as Scott Clark makes that very plain.