I got the iOS 13 too, but I haven't driven the car yet. Not worth the hassle to have the car brought down from the racks, so I can test it. Wednesday will be the day, when we go foliage peeping in the Catskills.
Please keep us posted on anything new about the settings.
Well, I took a trip down to the garage and played with it.
First off: Remove your car from CarPlay on your iPhone. You will gain applications and functionality if redo your connection to the car. Before I did so, when I first got into Carmen, my iPhone automatically started up from off as usual, I punched in my PIN and after a while, CarPlay showed up. It only had the apps that were there before the upgrade. I hit the Porsche button and untethered the iPhone, and CarPlay, as you would expect, disappeared from the PCM menu. I removed my car from CarPlay on the iPhone, turned off the phone and plugged it back in with it still off. Left the car.
Waited a minute, went back to the car. Got in and opened the center console lid but the iPhone didn't automatically start up. Started the iPhone and closed the lid. Pushed the voice connection button on the stalk and CarPlay immediately showed up in the PCM. I pushed the CarPlay menu icon, and a message showed up that I needed to log in with the PIN on the phone. Did that, and CarPlay's menu showed up with the addition of at least the Calendar app and the Settings button. To get out of the car, I turned off the iPhone but, and this is interesting, the CarPlay button remains in the PCM. I'm assuming that means it will be active immediately when I turn the iPhone back on, of if I leave the iPhone on, it will tell me to use my PIN. I'll have to do my battery use experiment again to see if it still drains the iPhone if you don't turn it off. Kind of think it will.
There isn't much to the Settings menu item, but I did set the Dark to switch automatically on or off.
Here is a link to the brief tutorial on Apple's site.