just because they're listed a zeros at this point doesn't mean they're booked. the airlines may not have put a bunch of seats in these fare classes as of yet. i'm sure these fare codes are probably at zero's for next january at this point, and you know loads will be light then. a big part of this business is holding out on the lower fares until absolutely necessary. people are still selling seats for april, so they can hold out discounting june for another couple of weeks.