When will there be the possiblity for Linux users to preload the game?

How are patches going to be handled until the GoG Galaxy is available for Linux? I really don't want to download 22 gigabytes every time there is a new version :).

Sorry to disappoint you, but afaik the Linux version of TW3 is not even officially confirmed yet. We might not be seeing it for at least a couple of months. So, there will be no Linux version to preload, neither will there be one on May 19th...