I just tried your suggested search. All that came up was Main Cabin and Premium Economy. I was playing a bit with redemptions earlier today for tus-sez and tus-mle for dates in earlier november Nothing for tus-sez and for nothing for tus-mle (now). Earlier today I could only select coach options. If I tried one-way then I had around $700 in fees. Round trip was under $100. All very wierd.

edited to add I was trying to find Qatar flights.