Hurricane production was increased as part of a plan to create a reserve of attrition aircraft as well as re-equip existing squadrons and newly formed ones such as those of the Auxiliary Air Force. Expansion scheme E included a target of 500 fighters of all types by the start of 1938. By the time of the Munich Crisis, there were only two fully operational RAF squadrons of the planned 12 to be equipped with Hurricanes. By the time of the German invasion of Poland there were sixteen operational Hurricane squadrons as well as a further two more that were in the process of converting.