Gantt Suite for Jira v 4.0.x: Task deadline
A task deadline can be set via task edit dialog (double-click the task or select Edit from the task context menu).
Once a deadline is set, it is shown as a green arrow at the end of the deadline day.
In case a task deadline is failed, the red exclamation mark gets shown in the Flags column.
The deadline feature is only available if configured in chart settings (“Task deadline field” is selected in chart settings)