I don't make changes on my tickets routinely, so maybe this is something I missed. I had an H reervation, already ticketed, for YXU-MEL in December, with some intra Oz connections as well. For various reasons I needed to change the dates, the route (SYD rather than MEL), and cancel the internal flights. When I called AC to do this I was able to with no problem. What surprised me though, was when the agent had finished, he remarked that there was no change fee because it was an H fare. Expedia doesn't list any penalty, but I wasn't aware that discounted tickets could be change fee expempt. What are the rules on this?