At least he is using some of the right wording. There are two things that you need to do once you  complete construction of a system; commissioning and startup. Commissioning is testing of each component in the system to ensure that it works individually and is safe to operate. Startup is the ramoing up of production to full capacity. They follow sequentially, and startup can be almost instantaneous. Overall, I have seen these two activities take about 20% of the total duration of a project. In the case of P2O, given that it is maybe a 1-year job from start to finish, i would think that Commissioning and Startup could take a month or two. Startup alone a couple of weeks.

The fact that he uses the word mode is a bit of a problem. It implies an ongoing state of non-produciton, which is not the idea.