And the book was not explicitly marketed as being Part One of a mini-series.
Err, it's got a big title banner with Star Trek: The Fall
on it, and then the individual book title under that. So that does indicate that it's part of a sequence of books called The Fall
. Maybe it's not quite as explicit as a "Part One of Five" subtitle would be, but it's pretty clear just from the title that it's not a complete standalone.
As for marketing, just about everything I've seen online about The Fall
has promoted it as a 5-book series.