Ah! I see what you're saying. I agree, the marks are different, and please know that I'm GUESSING that this notation represents caesura. It's similar to what I recall from many years ago, and appears to correspond to what I found when I looked it up. I can't explain the above/below appearance of the symbol - perhaps to stand out visually against the repeat?
Perhaps there is a notation difference because of the alternate endings. It's as if there are two sets of railroad track symbols facing opposite directions but they are split apart, intermixed, and distributed to the two different repeat symbols.
Yes... I agree... I'm totally reaching on this one...
I can't find any reference material to support my fanciful interpretation.
"If I have seen further it is by standing on the shoulders of giants." -Sir Isaac Newton
Armin Hanika 56PF