Up until recently, when Bixby Voice was finally rolled out to 200 countries, the button could only be used to launch Bixby Home. Some third-party apps were able to sidestep the restrictions, but Samsung was quick to shut these down.
Now, the update will let users adjust whether the button launches Bixby Home or not. So it doesn't allow for full customisation, but it seems some users were accidentally launching Home, so the update will no doubt be welcome with open arms.
The toggle switch can be found at the top of the screen when you go into Bixby Home, or it can be adjusted in the Bixby Key area of the settings menu.
Bixby Home as a service isn't going anywhere, it can still be accessed by swiping to the left of the home screen, and Bixby Voice can still be activated by pressing and holding down the button.
It seems Bixby has had a bit of a torrid time since first being announced by Samsung. It's been developed to be much more than just a voice assistant. It can control virtually all aspects of the Galaxy S8 or Note 8, and will eventually be used to control other Samsung appliances such as the TV.
However the voice control feature, the main aspect of the service, wasn't available at launch and now the button to quick launch it is proving to be annoying for customers. It's good to see Samsung is listening to feedback and issuing updates to get around the problems.