It's really no set time but like 9 or 10 or when u c the police they'll let u know
Lawfully you can access the beach area until 8PM. But I've witnessed individuals still accessing the beach and parking areas well after midnight.
All day
I believe, technically, 10:00pm
Till the cops tell you to leave
You could stay at the beach you're entire night unless you are awake
I've seen persons on the beach as late as 2 am. Near by the muscle beach in Santa (Har)Monica. I do know who it why but saw a camper parked along Ocean Front walk. Which is a road supposedly closed to public use late at night right next to the Lifeguard Headquarters located at the bottom of Seaside Terrace.
24/7
Its open until 10pm
Parking ended at 8pm so at least until then I'm guessing.
Thanks! Your answer is awaiting moderation.