https://immi.homeaffairs.gov.au/form-listing/forms/1290.pdf
Ministerial discretions
1. If you were in Australia as an unlawful non-citizen during the 4 years immediately before making your application and it was as the result of an administrative error, then that period of time may be treated as a period of lawful residence in Australia.
2. If you were in Australia as a lawful non-citizen but not as a permanent resident as the result of an administrative error, then that period of time may be treated as a period of permanent residence.
3. If you were in Australia as a lawful non-citizen, but not as a permanent resident during the 12 months immediately before application, then that period of time may be treated as a period of permanent residence if you would otherwise suffer significant hardship or disadvantage.
4. Time spent in prison or a psychiatric institution by order of a court in the 4 years immediately before making your application may be counted as time in Australia if your conviction has been quashed.
5. If you are the spouse or de facto partner of an Australian citizen, or surviving spouse or de facto partner of an Australian citizen at the time you make your application, and you spent time outside Australia as a permanent resident in the 4 years immediately before making your
application, you may treat those periods of absence as timein Australia if, during each period of absence:
• you were the spouse or de facto partner of that Australian citizen, and
• they were an Australian citizen, and
• you maintained a close and continuing association with Australia.
6. If you spent time outside Australia as a permanent resident in the 12 months immediately before making your application, as the holder of an interdependent visa and your interdependent partner was an Australian citizen during your periods of absence, you may treat those periods of absence as time in Australia if you had a close and continuing association with Australia during those periods of absence.