The scheduling mechanism can align or adjust the start/end dates of tasks assigned to a Box with the start/end dates of the Box.
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A task can be aligned with a Timebox created using the Overview - Views - Hierarchy (Timebox = a sub-Box such as Iteration or Project Increment that doesn't have its own scope, as it's used to organize tasks within the parent).
Fields mapped as start and end date are affected by a task being placed in one of the Boxes and start/finish on the same date
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