Yes it was and the time line for the five stages was five years,...

Yes it was and the time line for the five stages was five years, Stage 5 being commercialisation.

From what I can see, during Stage 4 a fully operational device will be tested firstly at a sheltered site, then at a fully exposed site.

Stage 4 is forecast to be completed between 12 to 36 months after the start of the programme. That means commissioning would be in 2017, which is what they have forecast.