Promotion Fields Last Update Date - How it works?

Summary:

Hello,

Could you please confirm how the Promotion Fields Last Update Date field works specifically whether this field only captures updates made to promotion related fields within the Workforce Compensation Plan, or does it also capture promotion changes made directly through the employee's assignment history outside of the compensation plan?

What I have noticed is that this field gets updated when a change is made from the worksheet. What I am encountering now is that it is picking up the current system date (the date I am processing the promotion on the worksheet) instead of the actual effective date of the employee's promotion.