Confluence Roadmap bars with incorrect duration and shifted to the left

In Confluence 5.8.6 roadmaps, bars show the incorrect duration around the March 2016 timeframe using the view by week display. Also, bars past this date will be shifted to the left by one week. This happens 100% of the time. The steps to reproduce are as follows:

1. Create a new confluence page and add a new roadmap. Delete all existing bars and markers.
2. Set the view by to weeks.
3. Set the date range from 2016-02-01 to 2016-04-30.
4. Create two bars.
5. Place the first bar starting the week of 07-Mar and ending 21-Mar (3 week duration)
6. Place the first bar starting the week of 28-Mar and ending 11-Apr (3 week duration)
7. Save the road map (click insert) and save the confluence page.
   Looking at the resulting diagram, the first bar will look like it has a duration of 2 weeks (instead of the 3 weeks). This only happened to bars around the 14-Mar week. All other bars past this point will be shifted to the left by one week as well.
   See attached screenshots.