On 2026-10-25, 77 posts in docs/posts/ carried dates between 2026-10-26 and 2026-11-15. Every one was committed on the 25th. They sat at the top of the feed, and their JSON-LD datePublished claimed a day that had not happened. The same defect had been logged on 24 October, when 20 posts were dated 2 to 4 days ahead, and nobody fixed it.
The front-matter check (platform/ci/check_post_frontmatter.py) already compared the date with the file name. It did not compare it with the calendar. It now fails any post dated more than one day after today (UTC, with a day of slack for writers ahead of UTC). The 77 posts are redated to 2026-10-25, their commit date, and cross-links updated.
Running the stricter check also found nine fresh posts with no description or tags, which are now filled in. The lesson is the usual one: a rule that lives only in prose gets broken at a rate of dozens a day.