Check out the cover of volume 15 of the manga Boruto: Naruto Next Generations. According to reports, the new pages are written by Masashi Kishimoto (Naruto) and illustrated by Mikio Ikemoto.
Check it out:
Therefore, the release in Japan will be on September 3rd. Panini publishes the manga in Brazil.
Finally, the story follows several years after the end of the Shinobi War, with Naruto's son, Boruto, about to enter the Chūnin Exams alongside Sarada Uchiha and the mysterious Mitsuki.