score:2
"Three months" means three calendar months.
Based on the itinerary above, the visa will start on 10 October 2017 (the day you enter Australia) and expires on 10 January 2018 (three months after the day you enter Australia). The time of day is ignored.
Once you have entered Australia, you can use the VEVO service to check the exact date the visa will expire.
Upvote:1
EVisitor visa is multiple entry, you can stay in australia for up to 3 months at a time. Within the year of validity you can enter all the wishes you want. On the Australian government's website you will find all the information.