You can use one PC to download the updates and then send them to a PC without an internet connection.
When you open Upgrade Studio, the application automatically checks if there is a newer version, if you have previously logged in with your username and password. You are then asked if you want to install the updates. After the newer version is installed, you can export the update and install it on another PC. You can also manually download a newer version of Upgrade Studio from within the application.