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.
The Youtini Expanded Universe Ranking system is a 1-5 scale that ranks EU book quality, difficulty, and importance. Books closer to Level 1 are easier to read and understand, more important, and of higher quality.
After a year of close shaves, Doctor Chelli Aphra is taking it easy and lying low. Probably herding banthas or something. She's smart like that, right? No, not really. The galaxy's shadiest archaeologist is back doing what she does best: busting into alien temples to steal horrifying weapons for huge profit. She just can't stop herself. But plenty of other people could. Powerful factions are watching closely: Rebel and Empire, familiar and strange - all calculating whether Aphra's more useful alive...or dead.