San Francisco boards from the lounge only for the 747 flight - not the A380 flight (and I don't think this has changed as part of the lounge's recent internal re-furb).

Chicago boards from the First/Gold lounge only - CLub World/Silver board from the gate. It's about 70/30 whether the flight actually ends up at the right gate for lounge boarding, in my experience. I have only ever done this on a 747/777 - not sure if the A380 flight also boards from the lounge at Chicago.