@scooter99I have written to both TNG (no response after 2 weeks)...

@scooter99I have written to both TNG (no response after 2 weeks) and NT Department of Industry, Tourism and Trade (DITT).
I received a few responses from DITT (below), however, it wasn't of much use or detail. The MMP has been with the DITT was nearly 7months but it sounds as though there is informal back and forth between DITT/TNG that doesn't constitute a formal stop of the clock.. Whatever that means.

There is no statutory time frame under the Mining Management Act 2001, for the assessment of a MMP. The aim is to have the assessment of a mine MMP completed in 3 months, depending on the complexity of it this may vary. Also, this timeframe does not include the time that the MMP is back with the Operator. When additional information are asked, and the document is back with the Operator, we stop the clock. In relation to the assessment of the TNG MMP we are in communication with the Operator.

The assessment and related communications, and where matters are at on the MMP, are between TNG and DITT at this stage
When a MMP is under assessment, our communications relate to meeting the requirements of a Mining Management Plan under the MMA, and may include seeking clarity on various related matters, and /or further information on environmental management systems.We do not formally stop the clock.