The condition 8558 on a visitor visa requires the applicant to stay in Australia for no more than 12 months in any 18 months period.
So for example, the applicant travels to Australia on the 01st of January 2018.
Your 18 month period starts from there. So that will end on – 30th of June 2019.
Within this 18 months, you just need to make sure that your stay is up to 12 months, or you will be in breach of this condition.
You have two options, either stay for the whole 12 months and depart or on your calendar mark the 18th month date, and from make sure you keep a track of entry and exit.
|01 Jan 2018 Starts the counter of Any 18 months, Must not stay more than 12 months|
|01 Jan 2018||Entry|
|01 June 2018||Exit (05 Months completed out of 12 months)|
|Out Side Australia||n/A|
|01 Aug 2018||Entry|
|01 March 2019||Exit (12 Months completed out of 12 months)|
|Must not arrive before 30 June 2019|