A rebel cell is formed on Kuat, the main planet in the Kuat system, still under control of Kuat of Kuat and not yet taken over by the Empire.
The time is a bit before 0 BBY, but there is an accordion of time; it seems from the end of episode 3 to now is somewhere between 17 and 40 or so years. But yes the Battle of Yavin is on the horizon.
The party starts taking jobs with Kuat Drive Yards KDY, so they can more easily sabotage…
Some reference material gathered to assist.