With QlikView Server serving the clients with the document you can set it up to refresh gracefully without the need to re-open the document.
Check the Server tab under Settings - Document Properties in QlikView.
So if you have document A opened via Server and the document A is reloaded by someone, QlikView Server will know that the document has been updated and load the new document in to memory and do a seamless switch, depending on the graceful refresh settings you use.
There should be more information on this in the reference manuals.
it's clear in the server arch. what i don'y understand is if it's possible with the developer version: if i batch reload (for example i launch a script to regenerate a qvd), and qlik is opened, the opened instance of qlik is able to verify that qvd is changed and reload it?