Not wishing ill of this particular contractor, but anyone who has been involved in bidding for competitive contracts KNOWS that the cheapest or the best is not necessarily the one that wins. I am willing to bet that the time factor was overestimated by LA or the State, whoever.
It was mentioned on KFI that the contractor only needed 24 hours to do the job. The rest was built in to accommodate problems. The governmental agencies pushed for the padded schedule. Some think it was to justify OT for city, state, LEO. and emergency workers. Cynical I know ;)