Hmmm..... I've not practiced that far. Ashtanga may be a resource for the different Suryas after A and B. Traditions are so different now. Power Yoga, being relatively young, doesn't always incorporate some of the classic poses. I know that C is also known as a lunar salute and also one of the classical flows. You would steeple the arms up from tadasana then bow forward (some people rest palms of the ground other people clasp hands behind the back keeping the arms straight), look up to flat back, step right leg back into low or high lunge doing slight backbend, transition to down dog, then come forward knees, chest chin to the earth, slide of the low cobra and then move back into downdog. Step the right foot forward into high lunge then step the left foot foward and bow, sweep up to slight backbend and repeat on the left. There are a lot of variations on this. Ashtanga will probably have all of the Suryas. Hmmmm.... working from halasana to sarvangasana..... there are ways to support these postures but I've never had to do the supported versions. I could describe them here but honestly, get good instruction from your yoga instructor about these poses. I know that some teachers don't feel comfortable teaching shoulder stand as it's very easy to injure the neck. Halasana would be performed before and after shoulder stand. Yoga journal is very good at describing poses in great anatomical detail. They're also good at giving the variations to build up to the poses. I would use them as a resource as well as your teacher. Shoulder stand comes very naturally to me but not to everybody. It is also a closing posture. I could go into details but I really think you should be guided by an instructor. It depends on the teacher for Power Yoga. Some teachers will teach shoulder stand and plow and others will not. I have even had several DVD's where shoulder stand is either done or not done. You get similar benefits from legs-up-the-wall. Again, ask for very detailed instruction as these two asanas are very challenging and you can get injured if not done correctly. Namaste

Hmmm..... I've not practiced that far. Ashtanga may be a resource for the different Suryas after A and B. Traditions are so different now. Power Yoga, being relatively young, doesn't always incorporate some of the classic poses. I know that C is also known as a lunar salute and also one of the classical flows. You would steeple the arms up from tadasana then bow forward (some people rest palms of the ground other people clasp hands behind the back keeping the arms straight), look up to flat back, step right leg back into low or high lunge doing slight backbend, transition to down dog, then come forward knees, chest chin to the earth, slide of the low cobra and then move back into downdog. Step the right foot forward into high lunge then step the left foot foward and bow, sweep up to slight backbend and repeat on the left. There are a lot of variations on this. Ashtanga will probably have all of the Suryas. Hmmmm.... working from halasana to sarvangasana..... there are ways to support these postures but I've never had to do the supported versions. I could describe them here but honestly, get good instruction from your yoga instructor about these poses. I know that some teachers don't feel comfortable teaching shoulder stand as it's very easy to injure the neck. Halasana would be performed before and after shoulder stand. Yoga journal is very good at describing poses in great anatomical detail. They're also good at giving the variations to build up to the poses. I would use them as a resource as well as your teacher. Shoulder stand comes very naturally to me but not to everybody. It is also a closing posture. I could go into details but I really think you should be guided by an instructor. It depends on the teacher for Power Yoga. Some teachers will teach shoulder stand and plow and others will not. I have even had several DVD's where shoulder stand is either done or not done. You get similar benefits from legs-up-the-wall. Again, ask for very detailed instruction as these two asanas are very challenging and you can get injured if not done correctly. Namaste

Ahh, the double post monster strikes again:)

Namaste!
Welcome to the group. Power Yoga is originally referred to classical Mysore Ashtanga, and the A and B Surya Namascar is from that tradition. I know many people that basically adjust or invent what works for their lesson or group. That is how so many variation occur.

In the traditional method as first coined "Power Yoga" the shoulder stand work you refer to is in the section we consider as "finishing postures" after you have completed most of the practice the shoulder stand sequence is after the back bends and before the head stand.
Years ago it was commonly taught to finish a Hatha Yoga class with the shoulder stand then final relaxation. In the 80's there started a hooplaa about neck safety and the blanket frenzy exploded and then people had to stack 2-3 blankets folded just so and that made people fear doing those poses. You do need to be placed correctly for safe execution, but wonderful healing and benefits can come from that posture! It is best to learn it from a very well experienced and qualified teacher, just to be sure!