DOH! Applied for my GE renewal back in March. At that time I managed to book an interview for Today (23/08) for 09.30, only now to find they don't open until 14:15 (!). No notification from them re. change in opening time! Scurrying around now to see what to do... :-(
(I did get lots of emails from them about enrolling upon arrival in the US though - not much use at the moment).