In this talk, Dena will explain why ecommerce migrations still lead to a traffic cliff dive, even when teams believe the basics are covered. Drawing on real agency-side migrations and her work advising developers, she will show how to build a redirect map that holds up in practice, read crawl and indexing signals in GSC before and after launch, and get the technical checks developers often skip into the build. She will also share how to talk to clients about migrations without losing their confidence. Attendees will leave with a practical pre-launch and post-launch checklist and a framework for communicating technical risk without causing panic.