The retraction cites a revision number

The story went out at 14:02 with a wrong figure. The corrections policy says readers get to see what was published, not only what the page says now.

The article is a document node in the newsroom's notebook, and every edit cycle produced a revision. The desk fixes the figure; that is revision 9. GET versions lists them, newest first, with who and when. GET versions/{id} returns revision 8 in full, the one that ran at 14:02, exactly as it was. The correction notice links to it.

If the fix itself was wrong, restore puts revision 8 back as the current text, and the restore is itself a new revision, so nothing in the history is overwritten.

No CMS plugin, no "save a copy before editing", no screenshot of the old page in a Slack thread.