HMRC are withdrawing CHIEF entry access over 2 stages, it has been confirmed recently. The CHIEF system will be replaced by the Customs Declaration Service (CDS), which will serve as the UK's single customs platform for all HMRC declarations.
30th September 2022 – the ability to make Import Declarations on CHIEF will end
31st March 2023 – the ability to make Export Declarations an CHIEF and the National Export System (NES) will end
HMRC & BIFA will announce further information on the exact arrangements for withdrawing CHIEF services in due course.