I guess I had good timing, I knew there was a good reason their website was down so long last night! Few more questions regarding the chart (sorry, I'm still completely new to deciphering these...) Is the chart for one-way or round-trip? Also, where they show fare class, is that to upgrade "from" that class to ExecFirst? Why would you upgrade from C/D, I thought AC doesn't have a true F product? And why would upgrading from Y/B use less points than upgrading from C/D?

Finally, for a given flight, how do I know what fare class it's in? Are all Tango Plus fares considered Y/B, and eligible for the upgrade?