In general, once a resignation has been lodged withdrawal may only be with the consent of the employer. My advice, therefore, is that resignation is deadly-serious business. Don't resign unless you mean it.
Whilst there are some potential exceptions, I cannot express forcefully enough how difficult it is to succeed with cases based on their invocation. It doesn't hurt to ask, however, so in that context, here are the three circumstances that might affect the validity of a resignation:
- emotional state,
- duress, or
- incapacity.
Duress For example, a threat that, "If you don't resign, we will fire you and withhold your accumulated super," might be regarded as duress.
Incapacity If, for example, an employee resigned while affected by a dis-inhibiting prescription medicine, that resignation might be invalid.
Popular, but practical, follow-up questions include:
- Is a resignation that gives less than the agreement or award-required notice still effective? Yes; but you may be subject to withheld wages, withheld accrued benefits, or even action at law.
- Can the employer rely on a verbal resignation? Yes; but as with all things verbal, there may be a disagreement about exactly what was said.
- If the employer has failed to confirm a resignation, is it still in force? Probably.
Revenge is sweet and not fattening
—Alfred Hitchcock (1899-1980)