Originally Posted by
Soulwind
Unstable =/= unusable.
It was datamined a while ago that the artifact UI will do some weird stuff (purely visual) after the final quest in Silithus. People also speculate that they will automatically reach max level, allowing everyone to enjoy the last few months of Legion content without worrying about their position in the AP "race".
Other than that, it's just a few quests and a new BG. I guess it's fun to add an ingame countdown, and it's likely they'll have similar ones for future patches and content releases.