Complex sentence: The regiment's involvement in the attack on Beersheba began at 18:00 on 30 October, when the ANZAC Mounted Division set off along the Wadi el Imshash, towards the village.
Split into simpler sentences: The regiment's involvement in the attack on Beersheba began at 18:00 on 30 October. When the ANZAC Mounted Division set off along the Wadi el Imshash, towards the village.