Editing the flattened outlines does not just change the curve but alters the flattening mapping (that is the whole area enclosed by the curve).
Click(Mean flattening flyout) to display theUser-defined Flattening dialog.
Use one of the following methods to define the flattening:
Select Inner or Outer depending on the shell that you want to edit or replace. The flattening outline that is selected automatically relects the option you selected. If necessary, select a different outline. Drag points on the shell to a new position.