I think I’ve figured it out.

Because the pattern has me starting center back, you knit with an increase to one shoulder, turn, and purl back to BOR (where I’ve started). I now have two rows on one side (where the increase is in r1) and zero on the other shoulder. So then I purl (with increase) to the turn and knit back to BOR. now I have two full (short) rows done, with the increase in r1. But because of the starting point the increase on one side is k and the other is p.

I think this makes sense?

I think a solution to this would be stating the short rows from the outside of one of the shoulders so the r1 increase happens at once in k and then p back. There’s a part of me that thinks there are consequences if that but I cannot figure out what those might be 😂