They have a publicly available progress tracker* that’s based off of their internal Jira. They only forecast one quarterly release at a time, though, so there’s no ultimate release date. Given the size and complexity of the project, I doubt they would be able to make an accurate forecast.
*I’m on mobile so can’t give you the URL, but searching “star citizen roadmap” should lead you to it.
*I’m on mobile so can’t give you the URL, but searching “star citizen roadmap” should lead you to it.