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.
Shortly after pledging his love to Tahl, she is killed in the midst of the crisis on New Apsolon. Qui-Gon will stop at nothing to put an end to the conflict and punish her killers–even if it takes him to the Dark Side. Obi-Wan struggles with his own bond with Qui-Gon, hoping to keep his Master from crossing a line from which he can never return. The secret rebels on New Apsolon are no longer the only danger for the Jedi; the battle is internal as well.
This is the climax of the series set on New Apsolon.