Here are the remaining release dates for the rest of the All The Pretty Monsters series and Dark Side series according to the audiobook publisher Tantor Media.
October 22, 2019 - Gypsy Moon, Book 4 in All The Pretty Monsters series
October 29, 2019 - Three Trials, Book 2 in the Dark Side series
November 5, 2019 - Gypsy Rising, Book 5 in All The Pretty Monsters series
November 26, 2019 - Two Trials, Book 3 in the Dark Side series
December 19, 2019 - One Apocalypse, Book 4 in the Dark Side series
January 14, 2020 - Gypsy Truths, Book 6 in All The Pretty Monsters series