Only tasks which are auto-scheduled will be pushed out to accommodate the total work of the task. Most likely,
- The resource(s) on task has a non-working exception due to which the task is pushed out.
- The resource availability is also a major factor.
Ideally, for auto-scheduled tasks, you are expected to enter the Start date and resource allocation or Duration.
The Finish date will be automatically calculated by the system.
However, if you do not wish your task dates to change, then change the task’s mode to manual. With this, the task dates are never touched by the system.