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.
Aphra's private investigation on behalf of Vader. Vader's investigation on behalf of the Empire. It all comes crashing together...with deadly results.