It was on sale at black library live.I'm guessing it will be released as a direct exclusive like Yarrick: Chains of Golgotha,The Masque of Vyle and Flesh Of Cretacia.
SHADOWSUN - The Last Of Kirku's Line
Commander Shadowsun, child of the famed Kiru and protege of the legendary Commander Puretide, is destined to lead the next phase of the Tau Empire's expansion... if she can survive the trials before her. Crash-landed on an enemy-held planet, with foes all around and a seemingly impossible mission to complete. Shadowsun is determined to achieve victory, even at the cost of her life. But when she receives a message that tears her world apart, Shadowsun must make a choice unthinkable to most Tau; to abandon her duty for the sake of family, or continue to fight for the Greater Good.