I'm flying BOS-LAX in a week on the 5pm flight and it would help me a lot, logistically, if I could check the bag in around 9 in the morning. I'd then leave the airport and return later for my flight. Would this be allowed? I'm in F if it matters.

I checked on aa.com, but the only baggage check in times they seem to list are the cutoffs: http://www.aa.com/i18n/travelInforma...horEvent=false --nothing about how long in advance I can check in. I would imply from that that if the check in desks are open then they'll take my bag? Thanks.