Ann: 100m Step Out Hole at Kavanagh Hits 45.4m @ 1.2% Copper, page-8

I think that the significance of this is that all lodes as they are being drilled are being determined to be "mineralisation open down-dip and along strike", so once the mine is successfully operating and producing income, the reserves can be increased each year (by a greater amount than is depleted) by further development drilling.
Of course the dip is fairly vertical so that means that over time the mine depth will need to increase, but for the first few years there seems to be extra reserves that are likely to be added at no greater depth than the EAS has initially contemplated.

PS
Do bring me back to earth if my thinking is too "magic Pudding".