"Crossroad Blues" points?

This is probably a Jon Meyers question (and the type question this group
was originally formed to answer but that's a discussion for a different
day)...

In the Bookfinder listings for this book, three points are mentioned for
a first state dust jacket. One is pretty simple as there is a blurb on
the back from James Hall. His "Red Sky at Night" is misidentified as
"Red Sky Night" but the other two terms are "seventeen" and "storm
front". Storm Front is listed as a W. L. Ripley title and if it is, why
is it a point? And what is "seventeen"? I'm missing something here and
I think some of you can tell me what it is. I'm in the process of
attempting to catalogue my books and want to ensure that nothing is
identified as a first if it isn't.

TIA,
Ann