Its not going to go anywhere until the light changes. The light is a physical constraint to the car's speed. Just wanting it, isn't enough. Soloman was willing to split the baby but the mother chose. Production doesn't know what to do until this choice is made.
Planning typically is done in phases.
Long range aggregate supply demand balances are used to strategically determine the utilization of existing capacity and whether new capacity needs to be authorized. Once a year, capital plans are reviewed for new products and adjustments to capacity for existing products. The decisions made during this planning step provides the available capacity and the basic structure of the supply chain. Sales and Operational Planning is performed once per month to monitor and adjust plans where incremental changes can be made. Changes to rail fleets, storage, contract capacity and major swings in raw material purchases will require three to five months.