Back in my pioneering days - early to mid 1970s - I don't think there was such a school--- certainly not in New Zealand.
I think they started it in the mid 70's...............maybe late 70's. To qualify to go, you had to agree to be sent to "where the need was greater". Many agreed, just so they could go to the school. And, you had to be invited...............it wasn't automatic that you would be invited just because you were a pioneer.