The 2016 version of C4R (Collaboration for Revit) is available now.
Click this to download or click the image for an overview
You'll need to visit your Subscription page to access the download to install it. Look at the Services page and it should be listed among whatever services you are entitled to. If you don't see it then you'll have to sort out your A360 account first.
This is the video they offer at the online help documentation site to explain how to initiate a project with C4R