EV of discovery just, page-152

The lightness of the oil will be more like the difference between $10 and $12/bbl, not 25. It's much more dependent on development costs and flow rates, neither of which we know yet. In the meantime I'll be sticking closer to the industry-accepted $10 figure, though you are of course free to use whatever you want.

You are however making two big errors in your valuation. Firstly 300 MMbbls is the OOIP, not the EUR, so you need to divide by 3. Secondly, it's the P10 case, not the P50 or Pmean. So divide it by at least 2 again. Then multiply it by your risk factor. That might be 0.6 or so now that oil is confirmed. Still some risk around reservoir and commerciality.

Agree it's odd that this one found oil where BP only found gas with some oil shows. The same depth and stratigraphic interval. Just goes to show you can never tell with geology!