Originally Posted by
Academic
I think the combinations all have to be in one class, so you could get two Tango+/Leisure fares such as Q and L, ....
That is my understanding, also. I have had success booking a Leisure combination of H and A fares. This was over a year ago when it was possible to use a combination of SWU and SSWU respectively on the route. This after waiting and watching for the lower fare classes to drop off until the H fare showed as available for one of the segments to book online.