Migration redirects without the spreadsheet day.
Paste your old and new URL lists (or point at old/new sitemaps, Screaming Frog or GSC exports) and RoutePatch shows a free proof: match counts, confidence bands and the rows that need human eyes. If the migration qualifies, $49 one-time gets a draft redirect map with Netlify _redirects and Vercel redirect rules for high-confidence rows only, needs-eyes rows held back, a map.csv and a capped verify.sh (mechanical HEAD checks). You review and deploy; it never writes to your host. Not SEO insurance. 14-day refund.