From our experience, 3 people that i know of made it through the whole of phase 1 (i.e. including SDM!), i was the only one to get to the interview. Of our group at phase 2 (4 of us), 2 got through to the interview. In the group the day before 2 got through to the interview and on the day before only 1 got to the interview. Of those, i believe only 1 passed (not me, sadly)!