3.1 alpha is likely some ways away. If you look at the Godot repo, there is not even a 3.1 branch yet. :)
The focus right now is on stamping out 3.0 bugs and there will likely be a Beta 2 release very soon now.
You can see what features are currently targeted for the 3.1 milestone by using the tag: https://github.com/godotengine/godot/milestone/7
However, many of these haven't yet had any work done on them.