I will shortly fly a transatlantic flight into JFK on a web special first class fare.
I have a continuation onward to LAX - the issue being that there is a 10+ hour wait on the web special.

There are multiple flights to LAX prior to my scheduled flight.
If I have checked luggage - is there a possibility to standby?
And would there be a cost to all of this last moment?

If I can standby, could someone explain to me how to go about this?
Thank you.