Just went through the JFK bid pack for this month. A bit over half the lines are 60 day lines, the rest 30. The 30 day lines are 15-17 days at a time. All but one of the 60 day lines have you go to work three times in the 60 days. The company owns you up to 34 days in a 60 day line. Could be three 11 day trips or a 4 day and a 16 and a 14. Never been MIA or ANC based but I've heard they have some shorter trips which work if you live in base.