WBS Gantt - What is the difference between Start Date and Star date fields?

[info_opc]

Hello, Why exist two fields for Start Date and End Date?

I have noted that if I used Start Date (D), this field works in the Gantt of one project, but if I create a Gantt from two projects for example, I have to use then Start date (d lower case).

It is possible use only one field?

Thanks

[Jenny]

Hi,

 
The problem mostly occurs with WBS Gantt-chart installed version 9.3 or earlier and upgrade to the ver 9.7 or above. This was caused by Plugin's update, Jira recreates the existing WGC fields at the time of Gantt first creation(it'd happen just this once).
Start Date(old custom fields)---> Start date(newly created field)
You can modify to Start date field at issue view setting but before you change, please make sure to let users who use the old custom fields to be aware, it could be impacted their Gantt-chart display. 

Kind regards,
Jennifer,