Complex sentence: Promotion came in 1907 when he became a substantive colonel at the beginning of the year, and later a temporary brigadier-general commanding the Staff College, Camberley, Surrey until 1910, when he became Director of Military Operations at the British War Office.
Split into simpler sentences: Promotion came in 1907 when he became a substantive colonel at the beginning of the year, and later a temporary brigadier-general commanding the Staff College, Camberley, Surrey. In 1910 he became Director of Military Operations at the British War Office.