This collection now holds 228,677 records drawn from WO 421 at The National Archives, Kew.
Most records relate to the discharge of over-age personnel who served during the Second World War (1939–1945), though the collection spans 1921–1959. It covers twelve corps, including the Royal Military Police, Royal Army Pay Corps, Royal Pioneer Corps, Intelligence Corps, and Non-Combatant Corps, among others.
Each service member has a packet that may contain attestation forms, statements of service, B102 tracer cards, and B103 service and casualty forms. Between them, these documents can provide name, birth date and place, occupation, height, weight, distinguishing marks, next of kin, nationality, religion, residence, marriage details, death details, enlistment and discharge dates, regiment, and service number. Medical and conduct forms were excluded for privacy reasons.
I found records indexed for people mentioned in the document, and index entries where the indexed number couldn’t be found in the linked document.