During his interview with Keanu Reeves for Knock Knock, Steve Weintrab over at Collider inquired about the John Wick 2 story details. You can go over to Collider and read the details. Also, Keanu confirmed that the start date still appears to be solid for the end of October.
Note: Scroll down below the article where Mr. Weintraub includes the full transcript of his interview with Keanu.