Typical Flight test regiment during World War II for "expediant" testing:
Phase I - Concept development - done by the contractors. Answers questions basic question of concept feasibililty. Rolls Royce/Supermarine/Hawker Sydney will conduct this testing
Phase II - Proof of concept by the accepting authority. The Air Ministry and the RAF will conduct this testing
Phase III - All issues uncovered during Phase II testing are addressed by contractors. In this case, Rolls Royce/Supermarine/Hawker Sydney will test and develop solutions to issues uncovered by the RAF during Phase II.
Phase IV -thorough evaluation of all the aircraft's operating characteristics. All publications are developed and operational testing commences.
Lets examine the documents Glider posted and put them in context of how testing development works to see if they fit.
Phase I testing results:
Phase II testing request for fuel:
Phase II results:
Logistical constraints...Fuel must be at all the airfields before any engine is approved operationally.
In otherwords, Phase IV testing cannot begin until there is fuel at the airfields:
While the Air Ministry gets the fuel supplies ready for Phase IV testing, Rolls Royce must complete Phase III testing and address all of the issues uncovered during the Air Ministry Phase II testing.
Here we see the Results of Rolls Royce/Supermarine/Hawker Sydney completion of Phase III:
Logistical constraints restrict conversion to aircraft undergoing cyclic Service Inspection.
The picture becomes much clearer as to why in June of 1940, the Spitfire Mk I Operating Notes, paragraph 1 were not updated to reflect the ability to use 100 Octane fuel operationally.