BBY/ABY is used to position items along the Star Wars Timeline. BBY refers to Before the Battle of Yavin. ABY refers to After the Battle of Yavin. The Battle of Yavin in Episode IV: A New Hope occured in 0 BBY/ABY.
Wraith Squadron, a hodge-podge strike team of last-chance rebels, is in pursuit of Warlord Zsinj and his Super Star Destroyer, Iron Fist. Han Solo is tasked with leading the Wraiths against Zsinj. Along the way, squadron member Lara Nostil's secret past comes back to haunt them. Plus, an army of sleeper agent droids!
It would be helpful to have an awarenesses of the characters heading into this story. The storyline begins in book 5 of the X:Wing series, Wraith Squadron.
Wraith Squadron: they are the Rebel Alliance's ultimate strike force. Sleek, swift, and deadly, they are the first in battle, the last line of defense. Now they must find and destroy a wily enemy more powerful than the Empire itself.
Their covert mission has been a success. The enemy has been vanquished. Or so they thought. The Super Star Destroyer Iron Fist somehow escaped destruction and with it the New Republic's greatest threat, the infamous warlord Zsinj. To defeat him, Wraith Squadron must join a combat task force led by the only man crafty enough to beat Zsinj at his own game: Han Solo.
But Zsinj knows the X-wing fighters' indomitable courage is both their greatest strength--and their greatest weakness. For even against the most overwhelming odds, the Rebels will fight to the death. And that will leave Zsinj the galaxy's unchallenged master!