Create a task that starts on the last day of the month. You will notice the bar starts from the next month. e.g .if task starts on 31st March, the bar starts from April.
Release : 15.9.1
Component : Clarity MUX UI Usability
This is working as designed. When the task start date is the last day of the month, visually on the timeline view using period: Months, the bar is actually just on the line between the 2 months which is accurate. If you go to the view options and change the period to 'Weeks' you will see the task bar appears in the correct time period.