With the Vline it does stay on the Vline input if when you turn your vehicle off it is on that setting. (There may be a setting in the OEM system though where you have to tell it not to default to a certain screen). I'm fairly certain the low speed cameras still work as designed, but I generally have that feature off. I'd have to test. I also have never had a 2nd phone option, so don't know if it "fails" to the 2nd phone. I can't imagine it wouldn't. And i want to say in the Carplay menu there appears to be a place where you could switch between phones, but once again, never tried this.When you first start the car, does it default to android auto interface? And if you use the low speed surround camera view does it default back to android auto when you speed up?