Glad you're thinking about the calendar. As soon as the tubes are installed the clock starts to run. We should have everything else that can be completed, such as exterior appliances, plumbing, etc., done and the superheater components ready to go back in before the first tube is installed. If we can lag the boiler and sheeth it before then we should do that too, though the hydro test needs to be accomodated.
Yes. Clearly it is a consideration that significantly impacts our planning but, as you are very aware, it is not strictly that the clock starts to run as soon as you start to install the tubes but that the date runs from the earlier of in service date or a year after starting to install the tubes. So, once we start tubing, we are driven to be in service within the year.
Obviously we aim to have no significant items to delay us once we start to tube. However, there is a great deal that cannot be started until we have the tubes in. We have to hydro test to prove the tubes are sealed before we can do anything like lagging or fitting the super heaters or accessories. ... and the patch is sort of critical to even the first hydro test.