While it was mentioned that the expansion was planned to occur before the year's end my guess would be this is not going to be the case since the 81 arc prices still haven't settled down and there is still not a reasonable gold sink in the game.

There are a lot more concerning things the devs should be and probably are focusing on doing first like phase 2 of the new vendor currencies. But again this is just a speculation who knows what could happen I sure would love a time machine so I could know what to hoard