If you are outside Australia when you are granted permanent residence, your grant notification will specify an initial entry date by which you must adhere to. This is almost always 12 months from the date of your police and medical checks.
More often than not, this date cannot be changed. However, you can come and go, once you have validated your visa, by entering Australia after visa grant. Many applicants are already in Australia, so no specific date has to be met.
For more information, please contact us.