Make timeline bars for releases on the built-in Portfolio Roadmap use the Release Start Date field

Currently the built-in Portfolio Roadmap uses the Release End Date field to plot the timeline bars but the beginning of the bar is based on the a date inherited from the earliest date of any child Features in the Release.

This leads to a messy, confusing Portfolio Roadmap that requires managing and maintaining dates at the granular Feature level where any moves/adds/changes to Features will immediately impact this high level stakeholder facing roadmap view.

Ideally the roadmap view could be configured to allow a choice of which date field is used to plot the timelines but at a minimum the view should render from the obvious Release Start Date field