I have a headache to QC on our product where there is a confusion when doing scheduler to manually enter with Start Date and End date. I roughly explain how the screen look like and where is my question lie in between.

In one screen there are appear to have two sections, the left section is called "Tasks" which to record down the summary of "Duration", "Start" and "End" date for the particular tasks.

The right section is called "Schedule". It is a section for creating a gantt chart. Our gantt chart is able to create by entry up data to the fields on a popup screen.

So it mean that when after a gantt chat or schedule is created on right screen, upon save the left screen will auto summary up the Duration, Start and finish date based on the schedule.

Question and Issue start here:
Please refer to image for easy reference.

When i am about to set a time range for a Task let say i know the date range is: 1 Jan 2014 - 31 Jan 2014 (where 31 Jan is the last day) but when enter for "End" date in the Task Information popup box, we need to plus one more day in order to end the time i.e. 1 Feb 2014. This is due to a limitation of the gantt chart , because of if 2 schedule create continuously the first schedule end point will be the second schedule start point. So that become a reason when we set end date , we always need to use next day start date . that why we fill End date = 1 Feb 2014. When we compare this value with the summary output for Finish date (where show 31 Jan 2014) user might start getting confuse here.

I Donno who expert here did ever QC like the scenarios that i hit above. When i told my SA team member i am not satisfy with the End date why every time enter it i need to remember to enter next day date. That create bad habit for usability. So i need any expert here to advice a better solution.