Gregg and Kathryn Brain, and their seven-year-old son Lachlan are now in limbo - after a deadline for them to meet UK visa requirements expired at midnight on Monday.
They told SBS they hope to seek further legal guidance to try to resolve their situation.
The Brains, from Brisbane, moved to Dingwall in 2011, planning to remain in the UK on a visa scheme designed to encourage migration to the region.
But since the government changed the rules in 2012 - scrapping the programme - they’ve been fighting to stay.
The couple both have Scottish roots, and had planned the move since spending their honeymoon there.
They say they invested their life savings to move to Dingwall.
“It's been a dream of ours since 2001,” Mrs Brain said, “This is not an overnight decision. This is something that we've planning for a very long time.”
Now, they say, they’re having to live off the kindness of others, and are being hosted by the local community, while they battle to stay.
"An easy visa pathway that was open to us and promised to us when we committed was torn up after we committed to coming here. We've invested six figure sums in the local economy,”
said Mr Brain.
The family moved to Scotland on Mrs Brain’s student visa - planning to stay on a post-study work visa scheme established to encourage migration to the Highlands.
The government scrapped that scheme in 2012.
The family has been granted three visa extensions, to allow Mrs Brain, an expert in Scottish history and archeology, to find a job that meets her current visa rules.
The offer of a temporary job at local distillery GlenWyvis was revoked last week, as it did not meet the requirements of Mrs Brain’s visa.
“We have really bent over backwards to do everything according to the home office program that was put before us,” she said.
“It really does boil down to simply asking the UK government to give us what they said they would,” Mr Brain added, “It is just a matter of simple truth and integrity.”
Their campaign to stay has attracted widespread local support, including thousands of signatures on a petition to the Home Office. Scottish First Minister Nicola Sturgeon has backed their bid, as have several Scottish National Party MPs.
MP Kate Forbes has pushed to change visa regulations, to establish a post-study work visa scheme.
“Not having one is costing the UK economy millions of pounds because students are being put off applying to the UK universities and then we're not being able to benefit from the talents of these students who come from overseas,” she said.
MP Ian Blackford raised the issue at Parliament in May, insisting the deportation was a human rights issue because their son Lachlan’s first language is Gaelic.
He said the UK government’s response was “frankly not good enough”.
In his final Prime Minister’s Questions, David Cameron acknowledged the challenges of Brain family’s situation.
“We have given them an extension until 1 August to put in an application for a work visa in the normal way, and I very much hope that will happen,” he told the House of Commons.
That deadline has now passed.
The British Home Office says they have not received any fresh application from or on behalf of the Brain family which would allow them to stay in the country.
"We have given the family three extensions on an exceptional basis over a number of months to allow them to try to secure a job that would allow them to meet the immigration rules, but this cannot be open-ended,” a Home Office spokesperson said.
"In line with established policy designed to apply evenly and fairly to everyone, anyone who is unable to regularise their stay is expected to leave the UK voluntarily.”
