If I understood correctly from the last community call, the master branch is now for 6.1.0 development.
However, the artifcats of master builds are versioned as 6.0.0.-rc. See e.g. here for an example of the latest build.
Info: Latest commit of master as of November 18: cb048ea9f4f7ccc3612141ee76f7937b9ca1c823