Melmoth - The headline and lead are confusing (blame the sub) but the story's pretty clear.
As for the testing: one issue is that the UK did not plan to pick the way to go with the carriers before the STOVL testing had been done. It's now getting late in the day shipwise and STOVL testing hasn't started. The arrival of the UK STOVL jets will in any case be far too late in the day to change course.