FYI - apparently, there was a computer/network issue last night and those with appointments at SFO were told to come back today (and put on some waiting list?). The wait list was not clearly communicated to the staff today. More agents/supervisors were called in to help get through the backlog from yesterday and those with appointments today. The agents were able to squeeze some of those from last night in with those who did have appointments.
BF waited 30 minutes after his time slot to be called in. Interview took about 5 minutes.