If the UK leaves the EU without a deal a UK AEO scheme will replace the EU AEO scheme of which the UK is currently part. The UK AEO scheme will continue to provide the same benefits that holders currently have under the EU AEO scheme in relation to UK customs obligations and procedures applying to import and export operations carried on in the UK.
Current guidance issued by the EU is that AEO authorisations issued by the UK will no longer be valid in the EU after exit day. Any benefits which currently rely on an EU member state recognising your AEO status will therefore not be retained.
Details of the benefits of AEO status can be found at: