Majors often command companies in the British Army. This major commanded something called D Squadron 23 SAS (regiment). A squadron in the US military is administratively equivalent to a battalion. Wonder if it’s the same in the British Army, or if it is somewhat smaller (like a company-size unit)?
From Wiki:
UK and Commonwealth
In the British Army and many Commonwealth armies, it is the counterpart of an infantry company or artillery battery. The designation is also used for company-sized units in the Special Air Service, Honourable Artillery Company, Royal Engineers, Royal Corps of Signals, Royal Army Medical Corps and Royal Logistic Corps, and formerly of the now defunct Royal Corps of Transport, as well as the Royal Marines.
Squadrons are commonly designated using letters or numbers (e.g. No. 1 Squadron or A Squadron). In some British Army units it is a tradition for squadrons to also be named after an important historical battle in which the regiment has taken part. In some special cases, squadrons can also be named after a unique honour which has been bestowed on the unit (e.g. The Queen’s Colour Squadron of the Royal Air Force’s RAF Regiment).
................ company-size unit from a reserve SAS unit.