What Duolingo score do you need for Polytechnic Institute Australia?

Both pages say English test results are valid for two years from the date of the results up to the date you start at the Institute, and that the most recent test supersedes all previous tests. So a later, lower Duolingo score would replace an earlier one that met the requirement. The pages give no Duolingo-specific instructions for sending scores.

For comparison, the same pages ask for IELTS Academic 6.0 with no band below 6.0 for the bachelor's, and 6.5 with no band below 6.0 for the Master of Business, while the Duolingo figure stays at 115 for both.

The course pages list other accepted English evidence, such as PTE Academic, Cambridge English and GCE A Levels with a C or better in English. For the Master of Business, PIA also describes special and alternative admission based on work experience.

Requirements vary by programme and change between admissions cycles. The score that binds you is the one on your PIA programme page and in your offer letter, so check it there before you book a test.