How often is SYLVIA reviewed?

Twice yearly, in spring and in late autumn, with filing required before any new deployment enters public service. Each review pairs technical testing with process checks across three areas: the provenance of every corpus added since the previous review and its traceability to specific model versions, the reproducibility of published benchmark results, and the technical robustness of deployments already in active service. Findings are submitted to the Ministry, deposited with the National Archives, and summarised in the programme's public status record.