My daughter attended for 7 or 8 years this will be the first year she's not going (due to moving on to full time training). The Audition is a normal ballet class and there are a number of auditions throughout the day. Quite a number Audition and they take about 30 (I think) in each of juniors, middles and seniors. These are split mostly by age but they do take ability into account. Every child has to audition every year and they don't automatically get a place because they've attended the previous year. My daughter loved it and learned a lot, once there they do a ballet class each time and a second subject which includes jazz, contemporary, musical theatre, flamenco etc. They have some excellent teachers each time too.
Good luck to your dd for her audition.