Trying to find a way onto CO2840 tomorrow from IAH to PNS. The flight currently shows as full on co.com and thus no SDC was offered during OLCI. Is there any benefit to calling tonight and asking to be added to the standby list or do I stand just as good a chance if I wait until I get to the airport (because all standbys are processed based on rank X minutes before departure?)? I'm Silver Elite and traveling on a W fare on CO2280.