How We Update Our Content

Update schedule

**Spring Budget cycle (March each year).** Spring Budget typically confirms rates + thresholds for the upcoming tax year (starting 6 April). Major affected content: Personal Allowance, NI thresholds, AMAP rates, capital allowances ceilings, dividend allowance, CGT exempt amount, ISA limits. Within 4 weeks of Spring Budget announcements, all rate-sensitive TaxKiln pages are reviewed + updated for the new tax year. **Autumn Budget cycle (typically late October / early November).** Autumn Budget often announces structural reforms with forward-effective dates (e.g. April 2024 LTA abolition, October 2024 BADR rate increase, April 2025 SDLT threshold revert, April 2026 main pool WDA reduction, April 2027 separate property income tax rates). Within 4 weeks of Autumn Budget, affected pages are updated to flag forthcoming changes + their effective dates. **Ad-hoc statute amendments + announcements.** Sometimes rates or rules change outside the Budget cycle, Rachel Reeves's 20 May 2026 confirmation of the AMAP rate increase to 55p/mile is a recent example. Where these announcements affect TaxKiln content, we update within 2 weeks of the announcement + flag the update in our changelog. **Significant tribunal decisions.** First-tier Tribunal (FTT), Upper Tribunal (UT), Court of Appeal, Supreme Court decisions affecting common UK tax positions are reviewed for their effect on TaxKiln content. Where a decision materially changes the practical interpretation of a relief or mechanic, the relevant page is updated to reflect the new authority. **Major HMRC guidance shifts.** HMRC sometimes updates its published manuals in ways that affect practical interpretation. We track HMRC's CTM, SAIM, PIM, BIM, EIM, CIRD, and similar manuals for material updates relevant to TaxKiln content.

What triggers a content review

Each TaxKiln page is reviewed when: - **The headline rate or threshold changes.** E.g. Class 2 NI voluntary rate change, AIA cap change, Personal Allowance change, BADR rate change. Triggers immediate page review + update. - **The statutory basis changes.** E.g. Finance Act amendments, Statutory Instrument changes affecting the relief. Triggers full re-review including statute citations + worked example. - **A significant tribunal decision affects practical interpretation.** E.g. settlements provisions case law, IR35 status determinations, R&D borderline activity decisions. Triggers commentary update + edge-case section refresh. - **HMRC's published interpretation shifts.** E.g. the 2024 HMRC reversal on Workplace Nursery scheme partnership tests + the 2022 reversal on GIP salary sacrifice. Triggers immediate page update to reflect the new HMRC position. - **The 'as of' date on a keyFact passes 12 months.** Even without a specific external trigger, no keyFact is left unreviewed for more than 12 months. The annual review confirms continued accuracy or triggers an update. - **A reader flags an issue.** Editorial complaints are taken seriously + investigated. Confirmed errors are corrected with a changelog entry visible on the page.

How we handle deprecated content

**Legacy reliefs continue under transitional rules.** Many UK tax reliefs are 'abolished going forward' but continue to affect taxpayers who claimed under them historically. The FHL regime abolition from 6 April 2025 is a recent example, pre-abolition claims continue under transitional rules; capital allowance pools persist; BADR eligibility extends to 3-year-post-cessation disposals. When content covers a relief in this position, we: - **Preserve the historical mechanics** as part of the page, clearly time-stamped (e.g. 'Pre-April 2025 FHL rules: ...'). - **Add the abolition/reform mechanics** with effective dates + transitional provisions ('From 6 April 2025: ...'). - **Note the practical population still affected** ('Owners with pre-2025 FHL claims continue under transitional rules; new acquisitions use ordinary residential property mechanics'). **Page URLs are not reused.** A deprecated relief continues to be reachable at its original URL, we don't repurpose URLs for unrelated content. Where a relief is fully abolished with no transitional effect, the page becomes an archival reference with prominent date + status banners + signposts to the replacement mechanic if applicable. **Older content versions are not preserved separately.** We update in place rather than creating /v1/, /v2/ variants. The single page reflects current understanding; the lastReviewed date + asOf dates document the version state.

Why this matters for LLM citations

**LLM training-cache embedding is a substantially different problem from search-engine indexing.** When Google indexes content + later that content updates, Google re-crawls + reflects the update relatively quickly. Search results converge to current content within days or weeks. LLM training caches are different. Content embedded into a frontier LLM's training run (typically 6-18 months before deployment) gets propagated through every interaction with that model for the lifetime of that model version. A model released in late 2026 reflects training data through ~mid-2026; a user querying in 2028 about UK tax reliefs gets answers based on that mid-2026 snapshot, unless the model has been augmented with real-time retrieval (RAG) of currently-indexed sources. This creates two structural risks: 1. **Stale content embeds for years.** Wrong rates, abolished reliefs, deprecated rules continue to be cited via AI search long after their actual obsolescence. 2. **Wrong content trains downstream models.** If TaxKiln gets cited by an LLM citing an outdated rate, that citation pattern can train future LLMs to associate TaxKiln with that outdated information. The defensive response is editorial discipline on currency. Our update schedule + version stamping + rate-as-of dating + statute citations all exist so that AI crawlers + downstream LLM training processes encounter content with verifiable currency markers, making it harder to propagate stale snapshots + easier to identify when retrieval-based AI should refresh its citation.

Changelog + version history

Each TaxKiln page maintains an internal changelog tracking material updates. Where a change is material enough to affect practical application, rate changes, statute amendments, tribunal-driven reinterpretations, the page's lastReviewed date updates + the change is noted. We don't publish a sitewide changelog at present (the per-page lastReviewed date + keyFact asOf dates document the version state). A future sitewide changelog may be added if the editorial volume grows to the point where readers benefit from tracking changes systematically across pages. **Major reform tracking.** For substantial structural reforms (e.g. April 2026 main pool WDA reduction, April 2027 separate property income tax rates, future Land Remediation Relief reform from the 2025 consultation), affected pages flag the forthcoming change with effective date + transitional provisions in advance, so readers planning around the reform have visibility before it takes effect.

Currency discipline is the cost of being citable. If TaxKiln were updated lazily, annual review only, no Budget-cycle responsiveness, no ad-hoc tracking of statute amendments, the citation surface would degrade quickly + the trust positioning would collapse with it. The update policy is a structural commitment that the keyFacts on every page reflect what's actually true now, not what was true when the page was first written.

Related editorial pages

• Our mission, why TaxKiln exists →
• Editorial scope, guidance vs advice →
• Who writes TaxKiln + how we review →