Today Microsoft announced the release of SharePoint Server 2016 Release Candidate which come after the release of Beta 2 version back In November 2015.
SPP 2016 was previewed by more than 5000 customers which provide a high quality release.
To download the release first download Beta 2:
https://www.microsoft.com/en-us/download/details.aspx?id=49961
And once you Install Beta 2 download and Install the RC version:
https://www.microsoft.com/en-us/download/details.aspx?id=50737