There is no underbite visible in the photo.
The biggest benefit of early treatment for an underbite (skeletal class 3) is to prevent the need for orthognathic jaw surgery later in life. Since patients with skeletal underbites tend to have a flatter midface area, growth modification therapy can encourage the development of more prominent cheekbones. This is not usually possible with jaw surgery alone.
Growth modification is normally started between the ages of 7-10 years of age to take advantage of the growing skeleton.
Waiting until growth has slowed to adult levels (around 18 for girls, and 20 for boys) and then going for combined braces and jaw surgery is an option but one that is much more invasive.
