The Third Booklet?

Hi, I’m reading The Desert Planet scenario book and at the end of the A Storm of Blades section, it references “the third booklet” The Sisterhood. What is this referring to? The book says this scenario is “all new” but was it pasted from another product? Does this third booklet exist?

Interesting. Hopefully it is referencing the next supplement on the Bene Gesserit but that’s been somewhat delayed (by all accounts) by setback to the production of the TV series - now called ‘Dune: Prophecy’. Apparently it’s coming late this year Dune: Prophecy - Wikipedia so we may see the new book shortly thereafter.

Its a misprint I’m afraid.
The work was originally destined for a different product and we missed one of the references in adjusting it for Desert Planet.
A BG book is on the list but the TV series has complicated that.