Well you said you encountered the same problem as samlonewolf, but that appears not to be the case as samlonewolf has succeded in downloading the off-line VPS Update file and gets this error when trying to install it.
You on the other hand appear to be having a problem with the on-line update, when using the avast UI ?
Whilst there will be a lot of server activity with the new updates - If there was a problem with the servers, then presumably samlonewolf wouldn't have been able to download the complete VPS Update file.
So I'm not clear what exactly your problem is.