SOP: Make lastmod trustworthy

SOP: Make lastmod trustworthy
Google ignores lastmod when it catches you lying. Run this audit.

Step 1 — Define what counts as a change. ✅ Only main-content edits update lastmod. Sidebar, footer, comment count, and ad rotations do NOT.

Step 2 — Use W3C Datetime format with timezone: 2026-06-13T14:32:00+00:00. ✅ No date-only strings on dynamic pages.

Step 3 — Spot-check 20 random URLs. ✅ lastmod within 24h of the actual last content edit in your CMS.

Step 4 — Fail condition: every URL shows today's date on every crawl. That means you're stamping build time, not edit time. Fix the generator.

Step 5 — Pages that never change (legal, about): freeze lastmod at last real edit. Don't bump it.

Definition of done: a random sample of 20 URLs matches CMS edit timestamps within one day, with zero pages showing a moving 'now' value.