Can't really think of any other than temperature override. It's not really in the owners manual. But you can get your hot tub up to 106.
So, when adjusting your temperature, you'll notice that you can keep clicking/tapping the temp up button till it gets to 104. Once at 104, just hold the temperature up button and after about 3 seconds, it should turn red and go to 105. Repeat to get up to 106.
I like my spa hot. It's at 105 now