Doesn't seem that the dev's have any intention to update the Linux/MAC version (yet?).
I texted them in the official Forum and they answered that i could download the game
directly at factorio.com.
This is quite annyoing in my opinion. If that would be done by all developers ppl here would require to "collect" the games through hunderds of 3rd party websites.
Just in case youre interested: https://forums.factorio.com/viewtopic.php?f=49&t=95590
Having to create an a separate account on their website just to get a patch is ridiculous, as is the notion that to use mods you need an account as well. It is dangerously close to having server mediated DRM. If nothing else, as roidal noted, we would need hundreds of accounts all over the place if all devs did this.
I sent a note to gog support a few days ago asking about MacOS and linux updates. When I receive a response, I’ll post it here.