<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by curiousflier:
I don't know about Jet Blue, but Southwest doesn't allow stand-by activity.
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If you miss your flight, you can stand by for the next flight. If you want to take an earlier flight, you need to upgrade to the unrestricted fare.
As a frequent WN traveler, it doesn't bother me too much. There's no change or cancellation fee, so (if it's personal travel) I just use half of a Rapid Rewards ticket and cancel my original reservation.