Forecast Consumption - Ship amount

We are using a weekly forecast consumption.  When a sales order ships early, the forecast is not getting consumed for the shipped amount because the pddj is updated with the actual pick date and ends up in the period prior to the week forecasted and in most cases in the past due, but it does not show in the past due.  The forecast still shows the shipped amount as not consumed and the planners see this as a required amount to order.  The planners are manually adjusting the forecast for each of these early ships.  The planners would like for