Yes, ORD is basically the same as CLT. The most jr FO is separated by 1 class. MAR 17 for CLT and APR 17 for ORD. So anyone hired after those classes could conceivably have bid, depending on equipment, and held any other base other than CLT or ORD. That being said it looks as though ORD has been harder to bid into for a recent hire(last 4yrs or so)over the last 3 vacancies, according to 3XP.