So I had fun enough riding one of her Lusitano geldings and continuing to learn to use the double bridle effectively... but then she popped me onto her Thoroughbred schoolmaster and casually had me take him through my first ever piaffe, passage, and flying changes! WHOA it was so awesome. There aren't words to describe. Obviously I was far from perfect with any of it, but I got to feel some of those higher level movements for the first time.
Needless to say, I am sooo excited to continue riding and working with my instructor.