Originally Posted by pykerl

Definitely had an issue with this the one time I booked through southwest.com and flew on Airtran (had a SW gift certificate to use up). They had 4-5 seats open in biz, so luckily the gate agent was really nice and tried for about 15 minutes (no joke!) trying to get it to work, to no avail.

Eventually she just wrote a new seat on my boarding pass, which was great, but I certainly was listed as my old seat in coach, since she could not get an actual upgrade to work.