Bumping this thread from last year as previous answers were speculation/observation. Has anyone had any recent experience with this or received any sort of confirmation about AC practices on this matter? I'm thinking of booking a flight with outbound in PY and return in Y, with the goal of eventually upgrading the return. Unfortunately there does not appear to be any IKK in PY, so am trying to figure out if a flight that is O9E9N0 has a good shot of eventually having more award inventory opening up, or if the numbers are meaningless as the cabin could actually be sold out (although I per earlier posts in this thread I believe it is unlikely that AC would oversell a premium cabin). I have several flight options on my return and would like to increase my odds of eventually getting PY on the return!