The Battle was obsolete by the start of the Second World War, but remained a front-line RAF bomber owing to a lack of a suitable replacement. On 2 September 1939, during the "Phoney War", 10 Battle squadrons were deployed to pre-selected airfields in France to form a portion of the vanguard of the British RAF Advanced Air Striking Force, which was independent of the similarly-tasked Army-led British Expeditionary Force. Once the Battles arrived, the aircraft were dispersed and efforts were made to camouflage or otherwise obscure their presence; the envisioned purpose of their deployment had been that, in the event of German commencement of bombing attacks, the Battles based in France could launch retaliatory raids upon Germany, specifically in the Ruhr valley region, and would benefit from their closer range than otherwise possible from the British mainland.