The objective when grouping components together is to be able to easily implement changes across all groups. This is mostly accomplished with how groups currently work in Revit. However, the "Phase Created" parameter does not update across all instances of a group. I don't believe this is in the intended design.
To recreate - create a group of components. Create multiple instances of the group. Go into the group to edit the group. Adjust the "Phase Created" parameter of one of the elements. Check another instance of that same group. Element that was previously changed in Group 1 was not carried over into Group 2.
Please confirm this is not the intention and fix in a future iteration.