FAQ n.124097

The Trade and Cooperation Agreement between UK and EU states that type certificates, supplemental type certificates, approvals for major changes, major repairs and technical standard order authorisations issued by the UK CAA or by a UK CAA approved design organisation will not be directly accepted by EASA and will be subject to technical validation by EASA. In some cases, when agreed by UK CAA and EASA, a streamlined validation may be performed.  
Further details can be found in ANNEX 30 AIRWORTHINESS AND ENVIRONMENT CERTIFICATION, Article 10.