Some interesting points made, and I guess a bit of an eye-opener...

I take back the point on spitefulness, it seems KQ have a combined per-flight and per time period quota, which is why when they released a set number of seats, it opened up availability on most flights and once these released seats were booked up no matter the date, the seat availability vanished on all flights. Seems unlikely to involve manual filtering / tinkering...

And on extortion, I guess that's just how business is conducted in the region when there is no real competition, it's take it or leave it and for as long as there will be sufficient takers this will continue!