Bu and Embla’s Guide to Starports of the Marches - PDF Released!

I have a question before I take the plunge on this book.
How many actual planets and ports are covered?

The title says "Guide to the starports of..".... but how many starports are covered?
Or, is this intended to be an on-going series? It does not seem so to me according to some of the comments I've read ehre
Thank you!
It turns out, late last night, I also found an episode of "Page102" on Youtube which covered the book and did a great job :D
I am working on read-through and creating a spreadsheet for the Worldbuilder's handbook right now....

But I do plan to buy this PDF soon and would love to see more Spinward Marches ports covered in follow on products!
(that work saves me time as a GM running campaigns in the Marches)