Grouping Records In Timeline Reports

I have a simple timeline report where i am list projects with grouping.  It works fine except for the fact that when I group records by clicking the little triangle I get the bars across months but I don't see the in store start and completion date as you normally would in MS Project . I raised this with Mark Shnier and now I am seeking help from others if this could be achieved.

As an example, have a look on the screen shot where I would like the red box to show in start and completion dates for the group so that it reports first start and last completion. .