Help Center Article
How to import a Checklist Template
To import a Checklist Template, go the Checklist tab in an Event and click the down arrow icon next to the blue Add Task button.
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You can import Checklists from Previous Events or use a Community Template.
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When you import a Checklist, you can automatically set the Task Due Dates to be the same of days away from the Event Start Date as they are in the Template.