Colvin's five-step migration route is: first use conditional create for opportunistic upgrades; then increase exposure of Passkey setup through in-app invitations; once analytics show that the vast majority of users already use Passkeys, require Passkeys for new users; then provide a clear option to delete the password (manual); then drive deletion through in-app notifications combined with educational copy; finally switch deletion from opt-in to opt-out, until the password flow is removed entirely.