What level would be on in ballet?

You might be fast at things like musical instruments but they don't need the physical training of dance...especially ballet. You need to discuss this with the school and teachers. If you haven't trained in two years, you will probably need to start at the beginning. If you prove you're past the beginning point, then you can always advance, but in reality, you really need to move fast and have extreme talent to get into competitive ballet. Those girls have never missed a class, and have already been training for years.