HorseSaddle English – https://horsesaddleshop.org/product-category/english-saddle/

The differences between the styles of Horse saddle English are small but significant. The most important distinctions are the location and therefore the balance of the seat, and the flap length and shape. A saddle used for a discipline where the rider sits more upright with a longer leg, such as in dressage, has a flap that is longer to accommodate the leg, and less inclined forward (as the knee does not need to go forward). The seat will also be closer to the withers, to keep the rider’s center of gravity in the correct spot. However, in disciplines where the rider needs shorter stirrups for better balance and security, such as in the jumping disciplines, the saddle flap is moved proportionately forward and shortened, and the seat is moved further back.