We should visually link milestones to the release phase that they are a part of both chronologically and by means of grouping. For example:
It should be as follows (chronologically and by means of grouping)
<RELEASE PHASE 1>
<RELEASE PHASE 2>
----------------------------------------------------------
As opposed to the below set up which currently displays chronologically only:
<RELEASE PHASE 1>
<RELEASE PHASE 2>