Agree with #6. Any of the carriers can do it and I would suggest CX or QF as well. As far as not seeing the booking, it doesnt matter all that much. They can get the routing from the original ticket and they need to re-input it to price it anyway. If they make a big deal about not seeing the original routing then its only becasue they are too lazy to redo it. CX actually uses their head during a reissue from my experience. They will create an entirely new routing with your changes as if you are creating the ticket from scratch and then they compare the tax charges for the new ticket to the old and charge you the difference. I have been told QF does the same, though its more computerized. Been a while since QF touched one of my tickets, though. And he is also right that CX will catch any rule violations. They are very, very good at it. I would not do it with Lan Chile for two reasons. First, their ground staff is too stubborn. Second, they have not done them often enough so they dont know the rules.