Genesis, Exodus.. I don't know anything. Just going by what the scholars say about doublets and the politics of Omri's reign.What was amended, exactly? I'm just curious.
Proteges and scribes may have added to some OT books. And perhaps even other prophets did, as with the book of Isaiah.
But if the faithful had to correct erroneous assumptions, and hence commence the long tedious task of rewriting a book from the point of the error forward, then he probably wasn't really that faithful.