We have a model that needs to go to to several processes, but when they leave the model, they need to complete the same two processes they went to at first (Processor 1, and Processor 2 or 4).
The flowitems that are leaving the system have a priority, that means if a flowitem arrives but there is a flowitem that is leaving, this one needs to be process first.
We dont know how to make a processor (Processor E1) to serve first the trucks (flowitems) that are leaving and then send them to the sink to leave the system, and then to process the trucks (flowitems) that are arriving to the system.
For more appreciation we have attach our model