The 5000 hours is not a hard and fast rule. With the market for pilots being what it is, they have relaxed the hour requirement for individuals who have built their hours doing interesting or challenging flying assignments. They recently finished interviews and hired for a class coming up at the end of the month (interviewee hours ranged from around 4,000 up to around 11k). They are looking into another class beginning in September, which will have the application window opening in June or July.