Hi Matt,
Sorry completely missed this one my friend, I didn't get an email notification!
Yes the sequence is just a "once-through" protocol. It's something which, in the beginning, we start of as having to develop capacity toward and, by the end, it just becomes a quick warm-up. Which is something I always love - seeing the stuff of developmental projects becoming "just" warm-ups!
So, I would just perform a single set of each as they're not really presented in this protocol for linearly-progressive capacity-development (not in the way that the isolated 'Active-hang' can follow its own thread to 'Active arch', which can itself branch off into chinup/pullup, or move forwrad to 'Arch & lever' which have then move to 'Front-lever'... The isometric active hang really is a scapular-stability staple, hence its recommendation for performing a set up to 2-3x per day if you really want to push devleopment forward).
You could, however, increase frequency of the sequence if you feel yourself lacking here - you can even plug it into priority 3-4x per week, FURTHER to beginning any upper-body/pulling session. Whilst they're different directions of movement, each is effectively hanging scapular mobilization so you should see the whole sequence as essentially 4-sets to itself.
Hope that sheds some light! Let me know if anything is not clear.
Wishing you the scap-stability of Rhino and the mobility of Falcon wings!
J