Hello 
Just to give you guys an idea of what is going on:
- Currently we are running into some issues with adding the latest achievements for Xbox in which we cannot confirm that they are working consistently.
The development team is working hard with Microsoft to resolve this issue! (As it appears to be more so within their realm of control.)
- Unfortunately, this does mean that we have no current ETA for the Xbox achievements.
And we greatly appreciate and thank you for your understanding and patience on this matter!