I was sitting at my PC having not long applied the recent updates to my Production hubs.... I wanted to change the mode of my home.... Opting for a more "relaxed" feel....
With the main screen open in my browser for the updated hubs I clicked on the mode shown at the top of the screen and then wanted / tried to click on the mode I wanted to transition to....
I eventually figured out there was an "Activate" button on the right with a tick icon, which I would be happy to see stay, but I would also like to see clicking on the mode name also produce the same outcome of a prompt being displayed confirming the transition to the selected mode.