Thanks I'll try that next time.The off button isn't disabled. If you turn it off, when you turn on AS/AP then it cuts the auto wipers back on (saying something like it is needed for AS/AP). However, all you then have to do is cut the wipers off again, similar to the automatic high beam. What the S3XY buttons do is automate this for you, so when you set a button to turn AS/AP on, it cuts the wipers off for you, so that you don't have to do it manually, so one touch and it is all done. But the buttons merely (conveniently) turn the multiple steps into a button push.
Update on S3XY buttons, $200 USD and currently only good for Fremont assembled MY's. If you have an Austin assembled MY they aren't working for the moment at least. Mine is Fremont assembled but I'm not about to start spending dollars to fix or correct basic functionality I'd rather spend my energy harassing Tesla about it till they fix it...