There was a post over on Battlechat about a leak found on d.163.com regarding a release date for Diablo Immortal to be on October 25th. One week before Blizzcon 2019.
According to Battlechat the translation reads as this in English:
Diablo Immortal
Blizzard Entertainment and Netease jointly produced
11.4 Million people scheduled to go online, on October 25th.
Like with all leaks take them with a grain of salt. What do you guys think? Let us know in the comments and the forums.