Hi Sarah,
Didn't they give you a specific date you were suspended until? That's quite ambiguous.
In VIC the Interpretation of Legislation Act states that a month should be taken to mean a "calendar month". A calendar month begins on the day of your suspension and finishes the day prior to the same day the following month. For example if your license was suspended 22 May, 3 calendar months later would take you to 21 August.