Changelog for SQL Server Data Tools (SSDT) (i.e., https://msdn.microsoft.com/en-us/library/mt674925.aspx)
SSDT 16.5 (for SQL Server 2016)
Released: October 20, 2016
Build number: 14.0.61021.0
After installing 17.0 RC1 ... Help > About Microsoft Visual Studio I see ...
SQL Server Data Tools 14.0.61116.0
I do not find a Microsoft site that confirms or displays the Build Number for RC1
As stated in one of the release notes I can confirm that it appears that there is no side-by-side install of SSDT ... C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Visual Studio 2015 will open RC1 ... there is no 2nd VS icon
SOTATS, Inc.