My Sunset Limited train arrived 15 minutes early.
The afternoon before arrival,I asked the SCA what the procedure would be in Los Angeles. He confirmed that we could remain in one's accommodations until 6:30 A. M., but he did, gently, indicate that doing so would delay his departure from his job. (The gentleman was #3 in service attitude of the 3 SCAs I had on my Amtrak trip.) From my experience, I am sure with all of the noise and movement taking place within the car upon arrival at LAUS, one would be awakened. I am of the impression that everyone was out of the Sleeping Car within 15 mintes or so after arrival. (It took quite some time to get a Red Cap and I saw no one else leaving the train when a Red Cap was finally available.)