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Hover over the task.
Grab one of the icons that showed up.
Move the mouse over the desired day while holding the left mouse button.
Let go of the left mouse button when you reach the desired day.
The task duration should be changed now.
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After you finish working with the plan, make sure to save the changes. At the top of the page, next to the Plan’s name you will see a notification whether there are any unsaved changes.
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If you see the label, simply click Save Plan. You will also be notified that the changes are not saved in a pop-up when you try to exit the page.
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