There are times that the dates on tasks can change unexpectedly without any user manually updating the date reason. If you audit date attributes, they may show last updated by an administrator account.

Steps to Reproduce:

Prerequisite: Check Allow Effort Task Creation in Administration->Project Management->Settings

1. Create a project with project dates in the past (Ensure track mode is set to PPM and the project is Open for Time Entry)
2. Add at least one resource to the Team tab of the project (This will create the effort task and automatically assign the resource to the task)
3. Post a timesheet for a date that is past the current project dates

Expected Results: Task dates don't change if time hasn't been submitted against them

Actual Results: Review the task date and the dates should change based on the new actuals-thru date

This is working as currently designed, see more details below.

Release: ESPCLA99000-13.2-Clarity-Extended Support Plus
Component:

The most likely reason for this is the actuals thru date on the task assignment is being updated. If the task assignment has ETC's this can affect the task dates. This can occur in the following scenario:

Note: Even if the timesheet that is posted does not contain any entries for the task, this issue can occur. The reason being is PPM will see that the resource posted time thru a specific date. As the task still has ETC on it, PPM will adjust the dates accordingly as it considers the task still open due to ETC remaining.

Workaround: The one option to workaround this behavior is to close the project for time entry by unchecking 'Open for Time Entry' at the project level.