https://www.slab.org.uk/guidance/the-importance-of-providing-reasons-for-special-urgency-in-the-body-of-the-application/
Each application is considered on its own individual facts and circumstances. It is crucial that your reasons for the special urgency are included within the body of the special urgency application form. Consideration of special urgency applications is a priority matter for the Applications Department, aiming to deal with these within two working days. It is your responsibility to identify clearly and concisely the special urgency and why steps need to be taken to protect your client’s position immediately.