Ann: Investor Presentation - September 2019, page-56

Hi Brombarb
I agree with the quote when talking geological success on prospects and note the quote is copied from the the GCOS  (Psg) section of the link, its worth noting that section only refers to prospects.
88e will test 3 prospects, and 4 discoveries with the Charlie I appraisal well.
When drilling an appraisal well, on a discovery that has not had a flow test, the categorisation is a bit murky as it advances into probability of completion or success, but it is a step further along the path.
Both 88e and Premier are quoting discoveries, so I am comfortable working on that basis.
This link has a reasonably simple definition of discovered, it appears to fit what we have been given
https://www.spe.org/industry/docs/GlossaryPetroleumReserves-ResourcesDefinitions_2005.pdf

Discovered
The term applied to a petroleum accumulation/reservoir whose existence has been determined by its actual penetration by a well, which has also clearly demonstrated the existence of moveable petroleum by flow to the surface or at least some recovery of a sample of petroleum. Log and/or core data may suffice for proof of existence of moveable petroleum if an analogous reservoir is available for comparison. (See also “Known Accumulation”: Petroleum quantities that are discovered are in “known accumulations” or “known reservoirs”.