2 examples from Australian Tax Office.
neither Medicare or voting a factor.
32. A person who had just completed tertiary studies decided to leave Australia for an unspecified period of time to work in one overseas country to gain work experience. Before leaving she closed all bank accounts except for a 5-year interest bearing deposit. She had no established home in Australia and no spouse or children in Australia. While she was forced to return to Australia within 18 months due to an illness, she was considered to be a non-resident as it was her original intention to remain outside Australia for an unspecified period of time and she was considered to have a permanent place of abode in the overseas country.
Result: non-resident.
The opposite conclusion would have been reached if she had intended to (and did) spend one year each in 2 countries and then had travelled for a further period of one year, making do in temporary or transitory accommodation in each country as she went. In that case she would not have a permanent place of abode in any of the overseas countries and would continue to be a resident of Australia.
Result: resident during the 3-year overseas stay.