Offline updates

How can I update my avast! for Linux without connecting the server to the internet?

On windows this is possible by downloading the updates as an executable and running that, but I can’t find anything like that for the linux version. I’m running avast! on a network that is not (and cannot be) connected to the internet.

download newer version and reinstall older one.
BTW: newer version will be released this week

for the latest 400.vps file:
http://files.avast.com/files/latest/400.vps