The Expo Construction Authority, which built the line, previously guessed that the train line would open in April or May of this year, but that’s not their call, so it is just a guess. Metro’s the one that decides when the rail line will open and so far they’re officially adamant that the opening day is still up in the air. There’s no word on when the Expo maintenance facility will be completed and handed over to Metro, but “some observers” are betting that it happens sometime later this month. Whenever it occurs, it’ll kick off a chain reaction that ends in the big reveal of the Expo Line’s opening day, and then of course, opening day itself..