3 years before the Battle of Yavin, after an extensive search for a secure world to house their base, the rebellion managed to cross-reference Republic and Lasat star maps and found that the moon of Berzite in the Yost system was a suitable world. However, the trip was delayed as the rebellion's stolen Imperial cruiser-carrier did not have enough fuel to make the journey, and so the Spectres traveled to Horizon Base to steal the fuel. There, one of the rebels, an astromech droid named "Chopper", was separated and stowed away aboard an Imperial cargo ship. He soon befriended a protocol droid name AP-5 and together they managed to steal the vessel. Upon hearing the rebels planned on stationing their base in the Yost system, AP-5 warned them the Empire had recently set a trap there for the rebels, the droid instead recommended the planet Atollon.