Even better, the years may go on beyond three years into the...

Even better, the years may go on beyond three years into the long term ie life of Curragh mine is expected to be at least another 20 years ..

In December 2015 Wesfarmers (which operates the mine) published a 206 page report on the extension :
“The Curragh Extension Project (the Project) is for the extension of open cut coal mining operations at Curragh Mine in four adjacent Mining Lease (ML) areas within Mineral Development License (MDL) 162 tenement and MDL 328 (for ML700006 only) (refer Figure 1). The addition of the Project to the Curragh Mine operation is not planned to increase the annual production but rather extend the life of mine. Based on existing approvals for the Curragh Mine, the expected life of mine is to 2030. The Project is to extend the life of the Curragh Mine to at least 2038.”
https://dilgpprd.blob.core.windows.net/general/rpi15-009-curraghext-supporting-report.pdf