Master controlled attribute change triggering needs approval change order for inventory organization

Summary:

Master controlled attribute change triggering needs approval change order for inventory organization when user is expented from change orders at master level.

Content (please ensure you mask any confidential information):

We have needs approval rules separately written for master organization and all the invnetory organization.
Additionally we have a condition which exempts a user from change order when changes made at master level. The same user is not exempted from changed orders at organization level.

Now when we make change for master controlled attribute at master level, system skips needs approval CO for master organization, however internally it is invoking change order for org level change. This is unexpected behaviour. Why system is invoking inventory org level change order when change is at master level and user is exempted.