March 14, 2017 Android Studio 2.4 Preview 1 is now available.
The release is available in the stable channel, so you can check for updates via Help > Check for Update... (on OSX, look in the Android Studio menu). This will download and install a patch rather than download a full IDE image.
If you check for updates it will tell you there is a new version of Android Studio 2.4 Preview 1 (build 171.3804684). This is the same build you already have installed. Please don't try to download it again. We will have a fix included in Android Studio 2.4 Preview 2.