I think you can be aware of rules at the time of moving, but the rules have changed alot since 2001.
On Feb 26 2001 the government changed social security law (note: not immigration law). They amended the "social security act" 1991 to state that only New Zealanders who arrived in Australia before Feb 26 2001 are considered permanent residents. And that Kiwis who arrived after 26 Feb 2001 are no longer permanent residents and not considered 'residents' of Australia for the purposes of social security law. At the same time, the "Citizenship Act" was amended to state that Kiwis arriving after 26 February 2001 can no longer apply for citizenship, as in, a Special Category Visa given after that date is no longer considered a permanent visa for the purposes of the Citizenship Act (even though Kiwis who arrived before 26 Feb 2001 have exactly the same visa!).
So the only change that happened was in regards to social security payments/welfare and citizenship were blocked. It was not an immigration change, or a visa change, all New Zealanders are in the same visa group - the terms 'Protected' and 'Non-Protected' don't exist in the Migration Act and are only a product of the Social Security Act 2001.
So beginning Feb 27 2001, those Kiwis moving to Australia became ineligible for most government payments, and not being considered permanent residents in the citizenship act means their visa remains "indefinitely temporary". SuddenlyAustralian-born children of New Zealanders no longer acquired citizenship, because his/her parents aren't "permanent residents" of Australia. The children now have wait until age 10 for citizenship to be given.
The solution sold to the public was that if New Zealanders wanted to be treated equally, they could apply for a "Permanent Visa," like any other foreigner has to do before they enter Australia. (Prior to 2001 New Zealanders were actually not allowed to apply for these visas because the government correctly considered them permanent residents).
In 2005 the Australian Government decided that it would only give student loans to Australian Citizens. This change in policy means that New Zealanders moving after Feb 26 2001 (even their children) aren't eligible for HECS funding, and because they also aren't eligible for citizenship they are denied access to education. This was never a part of the 2001 changes and was the beginning of barriers being thrust up.
In 2007 the Australian Government abolished three specific New Zealand permanent resident visas (Skilled — Onshore Independent New Zealand Citizen; Skilled —Onshore Australian-sponsored New Zealand Citizen; and Skilled — Onshore Designated Area-sponsored New Zealand Citizen). New Zealanders can now only become "permanent residents" by sponsorship or competing with foreign migrants for capped numbers of skilled visas - the department of immigration estimates up to 60% of kiwis will never meet the skills or age requirements, especially the Kiwi children of New Zealanders who have no skills and access to education funding cut away from them.
In 2008 some Australian states saw that the Federal Government was able to discriminate against New Zealanders depending on their date of arrival (Before Feb 26 2001 "Protected" / After Feb 26 2001 "Non Protected") and joined in the fun. They basically copied the residency requirements of the Social Security Act 2001 changes and pasted them into their own state laws, retrospectively revoking the rights of New Zealanders who had already been resident in Australia for up to 7 years (now 13 years).
Queensland currently denies disability support to New Zealanders and their Australian born children who arrived/were born after Feb 26 2001. New South Wales denies Social and emergency housing to the same group. Western Australia tried to do this with their disability funding but were successfully sued and funding was restored in 2012. In Victoria, all New Zealand Citizens including primary and secondary educated school children are denied student concessions because they aren't considered "permanent residents" - this is currently going to court in June at the Victorian Civil and Administrative Tribunal.
New Zealand women fleeting domestic violence with their Australian children are denied carers payments and emergency housing while also being denied the ability to go back to New Zealand. They can't even access money from their own super funds early, because you have to be already receiving a Centrelink payment to do so, which New Zealanders are banned from
The (Supporting Australian Victims of Terrorism Overseas) Act 2012 excludes New Zealanders who arrived after 2001 meaning if they are injured or killed overseas, even their Australian Citizen children will not receive a payment because her parent wasn't a "resident" of Australia!!
And now the National Disability Insurance Scheme Act 2013 excludes New Zealanders who arrived after 2001. This is the NDIS which perversely, all New Zealanders will have to pay the tax levy to fund it, while those who moved in the last 13 years will be denied access to it.
Of note the "Taxation Act" considers all New Zealanders permanent residents. So the Australian Government is perfectly happy treating them as permanent residents when it suits them, and as 'temporary non-residents' when it doesn't.
Lots of Kiwis don't want to go home, because Australia is now their home and has been for many years. They have had children in Australia, and if both parents are not permanent residents then their children have to wait until they are 10yrs old before they can get citizenship.
It wouldn't be easy to just say lets go back to NZ if you have a house here, your children have never known NZ as home, all their friends are here, and you have no ties back in NZ.
