The official X (formerly Twitter) account of Akatsuki and Kadokawa's Hachigatsu no Cinderella Nine smartphone game announced on Thursday that the game will end its service on December 17 at 5:00 p.m. JST, and added that more details regarding the end service is on the in-game announcement page.
In the game, the player takes the role of an unnamed former little senior league baseball ace who lost his or her baseball career after suffering an unspecified injury. The character moves to his or her grandmother's hometown and enrolls in the local high school, resolved never to enter the world of baseball again. When the character meets Tsubasa Arihara, he or she is persuaded to be the manager of the school's baseball team, and to take the team to the high school nationals at Koshien.
In the game, players gather team members (there are over 50 characters in the game) and experience the team members' stories. Players also train the members to improve their skills, and take members to games to compete. Players then have to decide on the batting order.
The game's anime adaptation titled Cinderella Nine premiered in Japan in April 2019. Crunchyroll streamed the series as it aired. Sentai Filmworks licensed the anime in 2019. HIDIVE started streaming the series in 2020.
The franchise also has an original live-action series titled Hachigatsu wa Yoru no Batting Center de. (August is for Nights at the Batting Center) that premiered in July 2021. Additionally, the franchise has inspired the five-volume Hachigatsu no Cinderella Nine S manga.
Thanks to DokoMadeMo for the news tip.
Source: Hachigatsu no Cinderella Nine game's X/Twitter account