In order to use manual start manual start and finish dates within your chart, you need to enable to:
Go to Settings | Scheduling, scroll to Manual Scheduling, and select Allow manual scheduling.
Select the field(
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s)
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that will store the
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manual Start, Finish, and/or
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Milestone dates. You can select date or date/time fields.
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When manual scheduling is enabled:
If the selected scheduling fields already contain date values, Gantt will use
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those values to place tasks
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on the chart.
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If a scheduling field value is updated in Jira, tasks on the Gantt chart will be rescheduled accordingly.
Dragging a task in the Gantt chart will update its associated Start, Finish, or Milestone field.
To learn more about manually scheduling from within your Gantt chart, see Scheduling Tasks.
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If one of the selected fields has Date type and the other one has Date/Time type, they both will be treated as Date. |
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If you do not have access to the selected field, or the field has not been added to the appropriate screens in Jira, you may receive a /wiki/spaces/ strcloud3668803778 |
Read-only Values
Gantt allows you to adjust manual dates and/or work estimates simply by dragging and dropping task bars within your chart. Depending on which attribute you selected to represent these values, it may or may not be possible to update those values.
If you use a Formula to calculate a date, you will not be able to make manual updates to that date. In this case, Gantt configuration displays a "read-only" message near the field selector, and you receive an error if you try to drag a task to a new date within your chart.
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In some cases it will not be possible to update the value of a custom field (for example, if the custom field was not added to the Issue Screen, or you do not have edit permissions). When this occurs, Gantt will display a Jira flag to let you know. |
Use Sprints for Manual Scheduling
When the Use sprints for manual scheduling option is selected, tasks can be scheduled to begin and end based on sprint dates.
See Use Sprints for Manual Scheduling for more information.
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If you use a mix of date and date/time fields for start and finish dates, both be treated as date fields. |
Update both start and finish dates when dragging items
This option is only available when you have selected a manual scheduling field for both start and finish dates.
If this option is selected, dragging a taskbar to a new location on the timeline will update both its start and finish dates in Gantt and Jira.
If this option is not selected, only the start date will be updated. The finish date will continue to be automatically updated based on task estimates and dependency types.
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If you have only provided a manual scheduling field for the finish date, moving the task will update the finish date only. |
Use sprints for manual scheduling
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Using sprints for manual scheduling requires Jira Software. |
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When this option is enabled, all resolved tasks and issue-based milestones that are not scheduled manually will be scheduled using the issue resolution date as the Finish Datefinish date. 
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This does not affect tasks with manually -scheduled Start scheduled start or Finish finish dates, or manually - scheduled milestones - – those items will continue to be scheduled based on the attributes selected above.fields selected above.
Read-only Values
When manual scheduling is enabled, you can adjust task dates and work estimates by dragging task bars within your chart.
However, there are some instances where this is not possible:
You do not have permission to update the field, or the field was not added to the issues screen. When this occurs, Gantt will display a Jira flag to let you know.
You use a Formula to calculate the date, instead of a field. In this case, you will see "read-only" message below the field selector, and you will receive an error if you try to drag a task within your chart.
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