The 12V on top center of dash from what I was told is dealer set to either turn off or be on a 1-2 hour timer. Mine defaulted to off when the ignition is off.
The remaining USBs, the center lower dash and rear passenger are either 1 or 2 hour hot after doors are closed. They will reactivate the next time you open your doors or unlock the vehicle for another 1-2 hours. This was designed so you can leave your phone charging while you go to lunch for example, considered a convenience feature.
I have the Motorola Android auto wireless dongle, and I placed mine in the center lower dash USB, double sided tape just above the USB port, takes me only a moment to unplug it. Or just leave it plugged, the amount of energy it consumes is far less than say a plugged in cell phone for that 1 hour it stays on.