Migrating to custom domain - what happens to auth0 hosted login url?

Before migrating to using a custom domain, I wanted some clarity about what happens to users who have bookmarked the previous <tenant>.auth0.com url?

Will the old url

  • continue to work and log the user into the app as expected
  • redirect the user to the custom login domain if I update Application Login URI in applications>settings
  • suddenly stop working

Thanks