Originally Posted by nd_eric_77

I have noticed that within the past few months, the couple of times I have been put on a carrier which has a code share and/or alliance relationship with the original carrier, the change can be done by e-ticket (most recently, when I was put on a CO flight instead of my original DL one, they were able to do so via e-ticket; I assume this is because they are both SkyTeam & Codeshare partners). When I was put on a different carrier which was NOT in an alliance with Delta (FL for HOU-ATL), it had to be done via paper ticket.