As the documentation is somewhat ambiguous/lacking i have yet to discover how to delete/insert page objects from/to a pdf object, without the use of importpage.
I copied from one object to another because it's not nice to ruin your originals, which is something i tend to do more often than not, but no just that. It's also because i simply figured no other way to reorder the pages without simply inserting them into another file in the order i want.