https://www.slab.org.uk/faqs/special-reviews-2/
In exceptional circumstances, the CHQAC may instruct a special review be carried out at any time. For example, this may come from a complaint being investigated by the Law Society, or may follow on from issues identified by an onsite compliance audit.
A special review will be undertaken at our expense at the firm’s premises and will follow the procedure of an extended or final review.
If the firm passes a special review it will not be subject to another routine review until the next cycle. However it may be the subject of another special review at any time in exceptional circumstances.
If a special review is to be held, the reviewers allocated for this review will not have taken part in any previous review carried out on the firm in the current cycle.
If a firm fails a special review it will be subject to either an extended review or a final review depending on the stage reached in the process. It may, pending final review, be subject to further special review.