The first anniversary update has opened Anville Town and Black city, and we're all happy. Sure, Black city is a bit empty, but that's Game Freak's fault.
Anville town, however, was different. Much more like the game, that is:
now, however, after the second update for the anniversary, the train looks like this:
and if that's not enough, talking to the NPC's (which have increased throughout Unova, including Anville Town) you will find a worker who says, in the exact words:
I believe, in short, that the event has to do with travels into the future, and perhaps perhaps in other regions that are not only distant in space but also in time ..... like b / w 2 or HG / SS. In any case, congratulations on the solution, curious to see how it will be managed!