This SS has not yet been added to the PRA Rulebook. It is available on the Bank of England website, here.

https://www.bankofengland.co.uk/prudential-regulation/publication/2017/solvency-2-matching-adjustment-illiquid-unrated-assets-and-equity-release-mortgages-ss

Related links

Technical Provisions
PS10 24 - Review of Solvency II: Reform of the Matching Adjustment https://www.bankofengland.co.uk/prudential-regulation/publication/2024/june/review-of-solvency-ii-reform-of-the-matching-adjustment-policy-statement