New Zealand Prime Minister Jacinda Ardern announced earlier this month that a true two-way trans-Tasman bubble with Australia will start at 11.59pm on Sunday 18 April, with the first flights leaving and landing in New Zealand on Monday April 19.

But there are some strict rules travellers will have to abide by and not all airlines will fly across the ditch. And Ms Ardern has warned, the bubble could pop quickly if new outbreaks occur.

So what will the bubble actually look like?

What exactly is the trans-Tasman bubble?

The trans-Tasman bubble refers to the arrangements coming into place on April 19 for travel between New Zealand and Australia which will avoid quarantine at either end.

With COVID-19 being relatively contained in both countries, the travel path links the two countries which are both deemed as a low risk of the virus spreading, making it safe to offer quarantine-free travel.

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When will the trans-Tasman travel bubble start?

From today – Monday April 19 – the two-way bubble goes live. That means people can travel to Australia quarantine free from NZ, and vice versa for Aussies heading to Aotearoa.

Will I need a vaccine to travel?

No. Prime Minister Ardern has said there will be no vaccine requirement for travel under the trans-Tasman bubble.

When can I book my flights and who is flying?

Right now. Air New Zealand has significantly increased the number of flights from that date.

The airline has also scheduled new direct flights between Wellington and Sydney on that date. Air New Zealand is also set to launch a new route to coincide with the opening of the travel bubble, offering flights between Auckland and Hobart.

Qantas and Jetstar are also set to increase their flight schedule in time for the opening of the two-way bubble.

However, Virgin Australia is in no rush to restart its trans-Tasman schedule. It told news.com.au that it won’t begin flying across the ditch until at least September and then only to one airport.

“While the airline remains committed to trans-Tasman flying when the market fully recovers, we are mindful of evolving border requirements which add complexity to our business as we push ahead with plans to grow our core domestic Australia operations,” a spokesman said.

“For this reason, we have suspended the sale of most New Zealand services until 31 October 2021. A limited schedule for flights to and from Queenstown will remain available for booking from 18 September 2021.”

How many flights will there be on the trans-Tasman bubble launch day?

Air New Zealand will have 30 flights across the Tasman on Monday, carrying more than 5000 people.

Qantas has scheduled 25 flights, with another four from Jetstar, following the New Zealand government’s lifting of quarantine restrictions for Australian travellers.

Will there by any requirements to get into NZ from Australia?

There will be no requirements in terms of quarantine or proof of a test or vaccine, Ms Ardern said. But if a passenger has cold or flu symptoms they should not fly.

All passengers will have to wear a mask on the flight and they will need to download, complete and show they have NZ’s COVID Tracer app while in the country.

Travellers will also need to complete New Zealand’s online declaration form prior to arrival, and the same will need to be done for travellers entering Australia.

“Upon arrival in New Zealand, passengers will be taken through ‘green zones’ at the airport meaning there’ll be no contact with those arriving from other parts of the world and going into managed isolation or quarantine facilities,” Ms Ardern said.

They effectively means dividing the arrivals area of airports into two – with one section for Aussie flights and another for people coming from further afield.

Random temperature checks are also to be expected at NZ airports.

The green zone flights will only carry passengers who have not arrived from other nations other than Australia and NZ in the previous fortnight. Similarly, the planes will only be staffed by crew who have not worked on intercontinental flights recently.

Could the bubble be shut down?

Yes it could, depending on whether there is an outbreak within Australia. In the same way, Australia has the ability to shut down flights from NZ.

Ms Ardern said there would be three possible responses should an Aussie outbreak occur, dubbed “continue, pause or respond”.

“If a case is found that is quite clearly linked to a border worker in a quarantine facility and is well contained, you’ll likely see travel continue in the same way as you could see life continue if that happened here in Australia,” she said.

“If a case was found that was not clearly linked to the border, and a state responded by a short lockdown to identify more information, we’d likely pause flights from that state in the same way we would stop travel into and out of a region in New Zealand as if it was were going into a full lockdown.

“And if we saw multiple cases of unknown origin, we would likely suspend flights for a set period of time.”

If an outbreak did occur in Australia, those travelling to, or already in, NZ from the affected area might have to do one of four things. That could be simply to minor for symptoms, take a test, isolate on arrival for a time or “in some situations” go into 14-day quarantine.

Hypothetically, if Brisbane went into a short lockdown, the NZ government could quickly shut down travel to and from south east Queensland. But travel to other states, such as New South Wales and Victoria, could continue.

If the bubble burst, what does that mean for refunds?

Qantas has extended its “fly flexible” policy, offering customers who book flights before 31 July 2021 added flexibility with unlimited fee free date changes when travelling before 28 February 2022. Jetstar offers the option of purchasing FareCredit on bookings which allow passengers to cancel flights for any reason.

Air New Zealand’s international flexibility policy was recently extended so customers with flights scheduled to depart before 11:59pm on 31 December 2021 have the ability to opt into credit or make a change to the date or time of the flight with change fees waived, but a fare difference may still apply.

Where should I visit in New Zealand?

The most popular destinations to visit in New Zealand include Queenstown (especially during the ski season), Christchurch, Auckland and the capital, Wellington.