According to a tweet by YonkouProductions, JoJo’s Bizarre Adventure: Diamond is Unbreakable live-action movie will be released on 4 August, 2017.
Let’s wait for official announcement from the official twitter and site.
[Update] 15 December, 2016: @jojomovie_jp has made the official announcement ?
Thank you so much for the trans/news! I love seeing your updates on Twitter and on the site!! Your effort is very much appreciated~ ^^;;
Thank you for the lovely comment! We will continue to do our best here 😉