If a page needs to be deleted, you run into a circular issue, although easily fixed. Please follow these steps.
1) Rename the “slug” from /blah/ to /blah2/
Example: The point is to avoid a name conflict. The legacy page actually shouldn’t need to be renamed. You could add “-archive” or how ever you wish.
*Understand that deleting a page is really a “soft delete” meaning statusdetail=inactive and status=0
3) Use /redirect/ module to redirect from /blah/ to some other page.