How significant is the mine's life/quantity of the material...

How significant is the mine's life/quantity of the material worth when determining the tree value of a project, and therefore the likelihood of its completion? I ask because AVL's mine obviously is larger, and the recent resource update makes it even larger. I know that TMT will probably follow suit in the resource upgrade and also increase the overall size, but I imagine we'll still be at least 1/3 smaller. I also know that we've still got the stuff irrespective of what our neighbour does, and it certainly seems we're going to do very well nonetheless. Specifically though, could anyone with knowledge on the subject of mine life shed some insight. I was thinking for example that perhaps it doesn't matter too much because it's easy to move the equipment to new pits as they are discovered. Generally, does more of a resource make a large difference (assuming the same quality etc.).