Shapes can be modified in a number of ways, even after they have been solved and are 3D. You can:
• finish marking the edges, which may improve alignment, using the Shape Explorer
• delete an edge mark by selecting the mark on a photo in select mode and pressing the Del key on the keyboard
• move edge and vertex points by selecting the points while in select mode and dragging
• add refinement relations using the Add Relation tool on the main Add Shapes toolbar (with appropriate items selected in photos or the 3D viewer - see Selecting Shapes and Shape Parts for more information)
• delete relations by using the Shape Explorer Relation view and the Delete Relation tool on the Shape Explorer toolbar
• rename a shape by using the Shape Explorer and the Rename Shape tool on the Shape Explorer toolbar
•
If automatic/background processing is on
(‘processing man’ in Status Bars is
‘running’ 
) then any of these changes will cause all the
shapes (and sometimes the photo orientation) to recalculate to take the new
information into account.