Every 30 minutes, 10 minutes ride to hotel.
We had an 30 min option and that worked great for us
It is suppose to be every half hour. One of the drivers was very rude to a customer when I was in the waiting room one early morning.
I see the property representative state that their shuttle doesn't start until 4:08am. That will be too late for a 5:00am flight
Get an answer from Hotel Focus SFO staff and past guests.