Coachella set times are not finalized until just a few days before the festival begins. The logistics required to organize an event like Coachella are massive and require hundreds of hours of work. Festival staff need to coordinate the arrival and departure time of each band/artist/DJ. Flights and tour bus schedules are constantly changing, and therefore the final set times are sometimes delayed. (In 2010, a volcanic eruption in Iceland prevented many artists arriving via plane from Europe from attending the Coachella).
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