Oracle Planned Order not Editable

Basically, the Supply Planners start in the Material Workbench, usually under the Material Plan table and review each of their items in that form.  When they decide that they want to release a planned order they right click and drill to the Supplies and Demand screen so that they can make updates and released the planned order.  What they are seeing is that sometimes, when they drill to Supplies and Demands, they are not able to edit the planned order.  If they go back to the Material Plan and then back to the Supplies and Demand screen it seems to