When the first download content will be released?

[Sch@dows]

The √ indicates the reverse version exists, so there is less work required for these tracks as there does not need one to be created.

Well yes ... and no. If I remember correctly, the front and reverse (white and black) version of metropia were not exactly the same int Pulse. The same for several tracks with more or less modification (arc prime, Amphiseum, Fort Gale and Basilico).
That a point in which I was disappointed when HD was released. Reverse tracks had just minor adjustement to be played backwards, and even reverse tracks from the original game were not kept.