Hello. I'd like to standby for an earlier flight later this week and read online that it's $25 as long as the flight is within 6 hours. However I'm now booked on a 3:20pm and the earlier one is at 9am... So a 6 hour and 20min difference.

Will I be able to change my flight online vs going to the airport and potentially getting denied? Any suggestions? I have no alaska status but have aa gold status. Thanks guys.