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After the plan is created it’s still possible to edit its details. You can update the name and duration. Bare in mind that changing the start or end date may cause some tasks to fall outside of the new timeline. Such tasks will be either removed or shortened to fit the new range.To edit the plan you need to be either a Jira admin or a creator of this plan
Anyone who has access to the plan can edit plan’s details.
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To edit a plan you first need to open this plan’s page. There you will find an Edit details button.
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