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.
TIE Fighter Trouble is a young readers book in the Star Wars Rebels series from Disney–Lucasfilm Press. Ezra and Zeb dodge Imperial patrols while on a special mission from Hera.