The financial advisory firm Greenhill Caliburn identified three key areas of risk with NBN Co's corporate plan including rollout cost, take up rates and average revenue. Our interpolation between recent trends and indications in these three areas and projections in NBN Co’s corporate plan suggests a significant gap between NBN Co’s likely targets and projections in its corporate plan. Any short fall between actual results and planning targets should be apparent by the 2013 financial year. With an election due soon after that, this would provide an opportunity to revise the corporate plan, most likely by retaining copper based access for longer. Policy issues need to be considered in the context that copper will remain a component of high-speed broadband networks for much longer than envisaged in the current NBN corporate plan.