Property of the ScriptLine : Inserts.
Set this property to Ignore Sides if pages that should be appearing in the preview are not appearing. This can occur when the insertion rules are complex and rely heavily on the sidedness of the pages being inserted.
In the example above (2d/2p), a different number of pages are added at the end of each month to ensure that each month fits exactly within a 32-page signature.
Important : To avoid unpredictable results, you should resort to the use of Ignore Sides only in when dealing with splittable grids.