I would agree with the 5:00 am departure time. I believe in leaving yourself a little wiggle room just in case something goes wrong. Also presently there are a lot of very unhappy people with United at LAX. So if you are flying United be prepared for some frustration. We were herded into their supposed easy check in line for the Shuttle. It was anything but easy. We could not get the seating we needed. Especially with two ladies with walking impediments who did not need to be on the aisle waiting to be trampled by the mad rush. We had to check in at the gate and undo what they initially had us do at the easy check in. By that time we could only get one of them out of the mad rush with a window seat.