Yes, It boils down to whether you get a full year or is it prorated from your date of entry. You will not be taxed twice on your income from home, under the tax treaty Canada has with Australia, and it is taxed at source, you should file for Foreign Tax Credit.
- To claim your credit, once you have completed the Profile section of your return, at the top right corner of the screen you will see a "Find" icon, type in "Foreign Tax Credit" and it will open the form needed to claim your employment taxes paid in Australia - in the Foreign Employment Income section of that slip.