In Adobe Workfront, Planned Dates are the dates that project managers can manually modify. These dates represent the schedule that the project is expected to follow and can be adjusted based on project needs. Estimated and Projected Dates are automatically calculated by the system based on task progress and dependencies, and these cannot be manually modified directly by a project manager. The Projected date is influenced by changes in the actual completion rate of tasks, whereas the Planned Date is the baseline schedule.