I haven't read other articles on that matter but I guess one of the drivers here Airbus simply cannot deliver that many A320s/320Neos in time. I'm even more surprised they were able to secure 130x pre-Neo 320s... If you are regular size operator and ask Toulouse "can I buy a few more?" you will be allocated a slot for mid/late 2015 delivery, almost the same time when 320neo production starts.