However, artillery policy in the BEF was to withdraw heavy batteries from the divisions and group them into dedicated heavy artillery brigades, so the battery was immediately posted to VIII Brigade, RGA, in II Group, Heavy Artillery Reserve. II Group consisted of a variety of heavy and siege artillery and was tasked with Counter-battery fire for the Allies' forthcoming Artois Offensive. On the British front this opened with the Battle of Aubers Ridge on 9 May. The group was provided with Royal Flying Corps reconnaissance aircraft fitted with wireless to assist observation in the flat country. Unfortunately the weight of the artillery support was inadequate for the task in hand: the obsolescent 4.7-inch guns were so worn that in many cases the driving bands were stripped off the shells at the muzzle, resulting in extreme inaccuracy. In spite of the counter-battery fire, German guns were able to open up on the British trenches, which were soon packed with wounded men from the first attacking wave, and support troops waiting to follow up. A second attempt to attack in the afternoon was hampered by the shortage of artillery ammunition to repeat the bombardment.