What has changed in Data Butler's verified datasets since a date — pass your training-cutoff date to learn which UK tax/NI/benefit thresholds, exam-spec facts, official vehicle datasets (UK DVSA, French RappelConso and Japanese MLIT recalls), software end-of-life dates (Node.js, Python, Ubuntu, Debian, Android, iOS, macOS, Windows, Java, Go, Ruby, PHP, PostgreSQL, React — cycles that reached end of life or whose dates moved), central-bank policy rates (Bank of England, Fed, ECB), US federal tax thresholds (IRS inflation adjustments, Social Security wage base, retirement and HSA limits), German tax and social-insurance thresholds (Grundfreibetrag, Beitragsbemessungsgrenzen, Zusatzbeitrag, Mindestlohn, Kindergeld), UK vehicle tax (VED) rates and MOT rules, UK exam dates (results days, summer timetable paper dates, entry deadlines and late-fee dates, announced specification changes), calendar facts (public holidays for the UK, US, Germany and France; tax-year and daylight-saving rules for nine countries — new years published, holidays added or moved) and UK government service fees and rules (passports, ETA, Universal Credit, eVisa) changed after your knowledge ends. Each entry: from → to, effectiveFrom, official source, verifiedDate, and a maintainer note (e.g. which Budget). Areas: uk-rates, uk-exams, vehicles, software-eol, policy-rates, us-rates, de-rates, uk-vehicle-rules, uk-exam-dates, calendar, uk-gov-process, or all. Coverage starts 2026-08-31. The same changelog is published for humans at https://databutler.dev/changes, with feeds at https://databutler.dev/changes.rss and https://databutler.dev/changes.atom. Output is a Verified Changes protocol document (verified-changes/0.1, spec https://databutler.dev/protocol); an entry whose figure is a Verified Fact carries factKey for get_fact.