I can't help but wonder if the story here is that with no recruitment in the charters for a year or so all the existing FO's are getting up towards potential command hours (even though there are no command vacancies) so when the vacancies do open up the airlines need FO's that are prepared to spend a goodly amount of time in the right seat, i.e. people who will take a long time to reach the minimum hours requirement.
Just a thought
wizzy