A New Tax System (Goods and Services Tax Transition) Act 1999
Parts 2-5 and 4-5 of the GST Act, and any other provisions of the GST law so far as they relate to registration, apply on and after the day determined by the Commissioner (even if that day is before the commencement of the GST Act).
From that day, you may apply to be registered if you are entitled to do so under section 23-10 of the GST Act.(2)
However, you are not required to be registered before 1 June 2000.
On 1 May 2000, you start carrying on a business whose annual turnover meets the registration turnover threshold. Although you would normally be required to apply within 21 days, you can apply anytime before 1 June 2000. But if instead you start carrying on a business on 20 May, you have until 10 June (21 days later) to apply to be registered.