There were a lot of things to do before the division resumed its march. Soul shards had to be extracted from the carcasses of the Nightmare Creatures, the carcasses themselves had to be piled into mounds to clear the way for the vehicles. Usually, each would have been dressed to harvest useful materials — the hides and bones of the abominations were a precious resource, especially that of the Fallen ones.
However, no one had time to properly process the remains of the fearsome horde, so the corpses were simply discarded by the side of the road, doused in incendiary liquid, and burned.
The transports and artillery vehicles, damaged war platforms, and powered suits of mechanized infantry had to be checked and repaired. Spent ammunition had to be replaced, wounded had to be healed. Soldiers, both mundane and Awakened, needed time to rest and recover.