New process
All EU citizens ( and their families) in the UK, regardless of when they arrived, will, on the UK’s exit, need to obtain an immigration status in UK law. They will need to apply to the Home Office for permission to stay, which will be evidenced through a residence document « settled status » ( if 5 years residency in UK if not temporary residence permit). Those who already have residency rights in the UK will have their document « converted » free of charge, but will be subject to identity, criminality and security checks.