I've heard of it happening in the Ureweras. But, in the Kawekas, DoC keep a spreadsheet which the helicopter companies check on to make sure it doesn't. I think there is a similar system in the Ruahines. Sometimes it can be frustrating not getting to your preferred block. In the end its a free country; anyone can go anywhere especially by foot. It's in the chopper companies' interests to keep it organised and keep the customers satisfied, specially the established long term operators'.
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