Complex sentence: It was formed at a time a great deprivation for the prisoner's of war and during this time Changi POW camp was being used to supply men into work camps in Malaya, Thailand and Burma leading to churn in members.
Split into simpler sentences: It was formed at a time of a great deprivation for the prisoners of war. During this time Changi POW camp was being used to supply men into work camps in Malaya, Thailand and Burma leading to churn in members.