UK nationals and their family members have a wide range of routes of redress and complaint available to them under the Withdrawal AgreementWithdrawal Agreement The Withdrawal Agreement sets out the terms of the UK’s withdrawal from the EU and provides for a deal on citizens’ rights. It sets out a transition period which lasts until 31 December 2020. During this time you can continue to live, work and study in the EU broadly as you did before 31 January 2020. If you are resident in Austria at the end of the transition period, you will be covered by the Withdrawal Agreement, and your rights will be protected for as long as you remain resident in Austria. Any rights that are not covered by the Withdrawal Agreement will be the subject of future negotiations. https://www.gov.uk/government/publications/new-withdrawal-agreement-and-political-declaration and elsewhere. These routes broadly mirror those currently available to UK nationals when exercising free movement rights in the EU.
UK nationals can complain to relevant public bodies in Member States and are granted a statutory right of appeal (administrative and judicial review) in their Member State of residence under the Withdrawal Agreement.
UK nationals will continue to have access to the European Commission’s complaints system; Your Europe Advice; CHAPs; the European Ombudsman; and “PETI”, the European Parliament’s Committee on Petitions.
The European Commission will continue to monitor compliance with EU law via complaints or on its own initiative. This includes rights under the Withdrawal Agreement.