Next Thursday I'm flying MCI-SEA through MSP. I noticed that I have a 4 hr layover in MSP and that there's an earlier MSP-SEA possibility. I've looked at the F seat map on this flight and it looks pretty wide open--much more open than coach. At what point can I be put on the stand-by list? Is it 6 hrs before the first flight of the itinerary or 6 hrs before my booked MSP-SEA flight? I'm hoping for an upgrade to F. Will the stand-by process look at both availabilities or only the coach, as that is the cabin booked?