Why do project planned start and planned end date fields get locked upon creation of a Decision record?

[mikej2]

Is it expected behavior that a Decision record (related list) on a Project will lock the Project planned start and planned end date fields?  I understand this behavior is expected (planned dates locked) once a project task is created, but I am seeing the same thing happen with no project tasks and only a decision record created.  Planned start and end are editable prior to the creation of the decision.  

[Dhiren Aghera]

Not an expected behavior at all. Before replying I did check the behavior in my PDI and RIDAC entries do not have any impact on the planned dates. The Planned dates remain editable unless you add a Project tasks. There might be some cusotmization in your instance. Can you please check with your ServiceNow team on the same.

[David-Ramirez]

Hi There,  

I believe this could be related to the Business Rule "Update parent rollup field" which sets the rollup field in a project which controls among other things if the planned start and planned end should become read only. this business rule should exclude Decisions as well as Requirements as per the following screenshot (line 7). This has been fixed in recent releases but maybe in your instance this could be different?