One last "the Long Earth" series book

[Helgathehairy]

I didn't realise there was another book coming out. I only read the series because of Terry Pratchett and I got the books from the library. I wonder how much TP was involved in this book.

Apparently the book was finished 18 months before Terry died.

I didn't realise there was another - it didn't feel terribly unfinished at the end of book 4.