Thanks Everett, I have the stretch series and do the thoracic bridge series once a week. I will continue slowly working on wrist flexibility and strength as you suggest via HS1/2 and F1.
With respect to F1 iMs, are you suggesting to incorporate some of the shoulder-related F1 iMs now? I tried the "jiao pengs" (spelling?) from HBP PE2>iM and PE3>iM, and it seems that both would help with shoulder rotation. It was notable though, that even without weight I had some clicking in what felt like the ribs underneath the scapula on my right side. It was uncomfortable, though not painful, making me think they are good exercises to correct some sort of deficiency I must have.
My general understanding is that starting iMs in advance of completing the earlier PEs is safe and productive, but attempting to skip ahead with PEs is advised against.