The press release says
"The engineering work went from 14 months on Cannonball to 13 on Mango, 11 on Cashima and 11 on Savonette. We expect the engineering work for our latest clone NUI, Serrette, to be completed in 9 months, which means that in just eight years, we have been able to reduce our platform engineering execution by five months, which of course translates into improved capital efficiency"How do we know this is a result of lessons learned? Well, we need to cross-reference to other publications, such as this one, where we read that
“Serrette is truly the culmination of the significant experience we have been gaining since 2001 when we began plans to construct our first platform locally, the Cannonball. By living the concept of continuous improvement, which is now being embedded across bpTT, we have taken the lessons from each project and applied it to the next project".The article goes on to describe some of the lessons incorporated into Serrette, and claims that the value of saved time can be in the order of $500k to $1m per day.
The five Trinidad platforms account for a total of 58 months in engineering, which would have been 70 months with no learning (assuming they all took as long as the first). The 12 month savings represents a 17% time saving, and can be valued at between $180m and $360m in total.