I have implemented a system for publishing documents from a document library to a Document Centre. This uses a Send To Connection set up with the "Move and leave a link" option. When this is used the original item in the document library remains unchanged (all metadata including the item ID remains the same), but the file attached to it is replaced with an .aspx file containing a link to the document in the Document Centre. I have now been asked to implement a way of copying the document back from the Document Centre to the original document library. Basically, it should be like the reverse of "Move and leave a link" and replace the .aspx with the document.
I have been able to find the moved document in the Document Centre, there appears to be no way to update the file in the list item (the File property of the SPListItem is read-only).
Is there a way of doing this, or is it impossible to replace the file while keeping the rest of the list item intact (including item ID)? It looks like the Send To connection is capable of this but, of course, it's possible that it is using functionality that is unavailable through the Object Model.