You can only make a discovery decision once the year has become final, i.e. if
As there are any number of dates on which the NTC enquiry window can close, you may be able to make a discovery decision at a relatively early date. In particular, if the early closure of the SA enquiry window has resulted in the early closure of the NTC enquiry window also, you may be able to make a discovery decision before the standard closure date of the NTC enquiry window. But you will never be able to make a discovery decision before the standard opening date of the enquiry window, i.e. before the conclusive decision has been made.