I'm taking LAX-SYD in First, departing around 10.30pm. Is it possible for me to check in for that flight in the morning, when the LAX-JFK flight is operating? That will save me time checking my luggage later on, storing it at the hotel during the day, and having to pick it up later in the evening.

I know that it states check in opens 3.5 hours before the flight, but it doesn't explicitly say it forbids earlier check in than that.