If approved content changes before publication, start by preserving one representative example. It gives the investigation a concrete reference and makes the eventual correction easier to judge.
Find the likely cause
Final edits bypass the review record.
Treat this as an explanation to verify against the actual work. Look at the input, the relevant decision, and the final result together. If the evidence does not support this diagnosis, investigate the mismatch before applying a convenient but unrelated fix.
Make the targeted correction
Require rechecking material changes and preserve the approved version.
Human review is most valuable when it focuses on the claims, decisions, and contextual judgments that matter to the final reader.
Check that the repair worked
Compare the publishing file with the accepted draft.
Repeat the check on the final version that the reader or customer will encounter. An approved draft, a preview, and a published result can differ; the acceptance decision should concern the version people actually use.
Prevent the next related failure
A separate issue to watch for is this: human review becomes a rubber stamp. Provide the brief, sources, and explicit blocking defects.
Monitor the useful outcome
Track defects caught, defects missed, and review effort by content type.
Keep a short record of the original symptom, the evidence behind the diagnosis, and the result of the acceptance check. That record makes the solution reusable when the same condition appears again, without assuming that every superficially similar problem has the same cause.