Taken from the announcement on his channel (https://www.twitch.tv/followgrubby):
"Starting Tuesday August 4th, 23:00 CEST with a 3 hour segment, Grubby will do a HotS bootcamp every week for several weeks. DON’T miss it and bring yo questions as it’s gonna be a great way to learn HotS if you’ve never, or improve your level and knowledge if you have!"
Let's make it a worthwhile endeavor! :)