The failure mode is familiar: a new theme launches, everything 301s to the homepage, and six weeks later organic traffic looks like a cliff. The redesign gets blamed. The redirect map deserved the blame.

Inventory the URLs that exist, not the ones in the nav

Crawl the old site. Export Search Console pages with impressions. List WordPress posts, pages, and public archives. Theme demo URLs and cart pages can die; money pages cannot. If you cannot name the destination for a URL, do not send it home by default.

Map, then 301

Preserve slugs when the new information architecture allows it. When a URL must change, point it at the closest equivalent, not a vanity homepage. Gone pages (old shop leftovers, for example) can 410. That is cleaner than pretending they still exist.

Canonicals, sitemaps, and robots on day one

The new site should advertise its own canonical host. Submit the new sitemap. Confirm robots.txt is not blocking something you just spent money building. Keep the old property in Search Console until the replacement is clearly taking over.

DNS is not a checkbox

TTL, email records, and SSL at the new host are how launches turn into weekends. Analytics should fire on the new theme before you cut traffic over — clients have called this out as the difference between a migration and a disappearance.

Studio7 treats migrations as this kind of work. If your plan is “we will fix SEO after launch,” you are scheduling a second project to repair the first.