From: Migrant with permanent residence - eligibility
It seems in your circumstances you will be eligible to apply for citizenship in January 2018, provided you meet the other conditions.You must meet all of the following:
- have lived in Australia on a valid Australian visa for four years immediately before applying
- must have been a permanent resident for the 12 months immediately before making an application and not have been absent from Australia for more than one year in total, during the four year period, including no more than 90 days in the 12 months before applying.