Further to my question Will I clear customs in Honolulu or LAX?, If we have a 12-hour layover in Honolulu, are we able to arrive, get bags, clear customs, then re-check our luggage and then leave the airport for the 8-10 hours before we need to be back for our next flight? Or will we need to find some kind of day-stay hotel or luggage storage? Or are we just going to need to stay at the airport for 12 hours?
Once you clear immigration and customs in Hawaii, you can certainly leave the airport, with or without luggage.
Common practice is both a) airlines open bag acceptance at the same time they open the check-in customer counter, usually 3 hours or so before flight time, and b) if the second flight is on the same carrier, there's a bag drop station immediately after immigration and customs.
I don't know if Hawaiian's baggage drop counter will accept bags so long before the second flight; on the other hand, it's a long layover and you're on their ticket. Call Hawaiian and ask.