The legal implications of a demotion

As was said in Charlton v Eastern Australian Airlines Pty Ltd (2006)154 IR 239
“Unless the contract of employment or an applicable award or certified/workplace agreement authorises an employer to demote an employee, a demotion, not agreed to by the employee, that involves a significant reduction in remuneration will amount to a repudiation of the contract of employment. If that repudiation is accepted, either expressly or by conduct, then the contract of employment is terminated. If, in such circumstances, the demoted employee then remains in employment with the employer, this occurs pursuant to a new contract of employment in respect of the demoted position. It may be noted that where the employment continues with the employee allegedly acquiescing in a reduction in salary or other terms of employment, difficult questions may arise as to whether the continued employment involves the continuation of the original contract of employment (but with the employer breaching that contract by paying the reduced salary), a consensual variation of the terms of the original contract or the termination of the original contract and a substitution of a new contract of employment.”
And see Powell v Department of Economic Development, Jobs, Transport and Resources (until recently Department of Transport Planning and Local Infrastructure) (2016 FWC 2397 delivered 28 April 2016 per Gooley DP