Who grants the approval
Approval is granted and withdrawn by a competent authority — usually the local council, sometimes the Food Standards Agency itself. 400 appear in this register.
Who to contact, and about what
The FSA publishes the register, but it is the competent authority named against each establishment that granted the approval and can act on it. For most establishments that is the local council; the FSA is itself the competent authority for 1,331 of them, mainly slaughterhouses and large meat plants.
An authority gets a page here once 12 establishments have been approved under it since 2020. The rest stay searchable through the establishments themselves.