JetConnect is just an operating entity that Qantas created in order to base crews in NZ and take advantage of lower costs (i.e. lower salaries and other conditions maintained by QF mainline due to many years of unionisation).
The aircraft are the same Boeing 737-300 and 737-400 aircraft that used to operate QF domestic services - originally purchased by the old Australian Airlines before merging with Qantas. They have just been re-registered with NZ regos as they are operated by NZ-based JetConnect.
Now that the second Australian Airlines (with the Orange 767's) has stopped operating its own AO flights, Qantas will continue to use Australian Airlines as an operating entity for some international services in a similar manner to the way they use JetConnect and for the same reasons - lower costs due to different staff conditions. But again they are Qantas aircraft, Qantas flight numbers, Qantas marketed and branded flights.
Both JetConnect and Australian Airlines operated Qantas flights are Qantas flights for all intents and purposes, including FF earning for all Qantas and partner airline FF programs. They are OneWorld flights and qualify for all OneWorld benefits and fares such as OneWorld Explorer.
Think of it this way ... for any Qantas flight, Qantas can source the aircraft and crew from one of three operating entities:
- Qantas Mainline
- Australian Airlines (currently 767 international services)
- JetConnect (currently 737 NZ Domestic and Trans-Tasman services)
I believe they are maintaining Impulse Airlines as another operating entity, initially for the remaining 717 aircraft. But who knows just how they will use Impulse, Australian Airlines and JetConnect in the future.