Redirect Map for a Site Migration

Help me plan redirects for a site change/migration. WHAT'S CHANGING: [[CHANGE]] (new domain, URL structure, CMS, HTTPS, consolidation) KEY PAGES / URL PATTERNS: [[URL_PATTERNS]] Deliver: 1. A redirect strategy (old → new mapping logic) 2. Rules for handling patterns at scale (not one-by-one) 3. What must be 301 (not 302) and why 4. Redirect chains/loops to avoid 5. A pre-launch and post-launch checklist to preserve rankings 6. What to monitor for the first weeks Flag the migration mistakes that most often cause traffic loss.Copy