Complex sentence: By November 1915 the Force in Egypt was almost reduced to a training and reinforcement camp, with 60,000 troops in Egypt which were mainly details of formations fighting at Gallipoli and Anzacs in training.
Split into simpler sentences: By November 1915, the Force in Egypt had been reduced largely to a training and reinforcement camp. Although there were 60,000 troops in Egypt, these were mainly details of formations fighting at Gallipoli and Anzacs in training.