How should someone in their mid-20s spend a Friday night?...

How should someone in their mid-20s spend a Friday night? Probably, they should be enjoying life rather than testing a rather fraught demerger hypothesis about a mining junior he holds. In any case, I've done some more research.

From CXO's 12 October 2018 "Napperby Uranium Resource Update and Increase":

Cut-off gradesThe MRE for the Napperby Deposit has been reported at a cut-off grade of 200ppm U3O8, which represent the most likely cut-off compared to similar style deposits, but the choice will depend on economic assumptions to be determined by Feasibility Studies. The grade-tonnage curve shows the sensitivity of the resources to the cut-off grade (Figure 4).
A top cut of 2,500 ppm U3O8 was applied, based on results of statistical analysis and variography. Marenica’s U-pgradeTM technology has demonstrated on bench-scale to concentrate uranium by a factor of 50, while reducing the mass to 2% of the original feed, with process recovery >70%. To date, Langer Heinrich is the only deposit of this “calcrete style” to be developed and operated. Core believes it will able to take advantage of modern advances in beneficiation, such as optical and X-ray sorting, to develop a functional beneficiation technique. If these techniques prove successful, it is inevitable that a lower cut-off grade can be applied to mining. This is very important for Napperby, as the Grade-Tonnage curve is steep at lower grades, potentially increasing the economic uranium in the current wireframe (see Figure 1) to 12.88 Mlb at 50 ppm U3O8 cut-off (Figure 4). This is not inconceivable, as many calcrete resources are now estimated at these low cut-offs, for example, the Marenica Project resource is 276Mt at 94ppm U3O8 for 57 Mlb using a 50ppm cut-off.

Figure 4:

Using the data from the potential lower grade cut-off, a resource of 28.58Mt @ 0.0204% U3O8 could be inferred.