See Fair Work Act 2009 s.386
The term dismissed is defined in the Fair Work Act as a situation where:
A dismissal does NOT include where:
A person employed under a contract for a specified period of time, specified task or for the duration of a specified season and the employment comes to an end at the end of that period, could be considered to have been dismissed if a substantial purpose of the employment of the person under a contract of that kind was so that the employer could avoid their obligations under the unfair dismissal provisions of the Fair Work Act.
 Fair Work Act s.386(3); see also Khayam v Navitas English Pty Ltd t/a Navitas English  FWCFB 4092 (Ross J, Colman DP, Cirkovic C, 16 August 2017).