In the uc of change itinerary, "Customer selects the segment to change", i can't image how can the customer change the segment?
i saw many booking system, there is no one providing this function.
in the uc of prepare itinerary, when customer enter departure and return city, the system return the list of fitting itinerary, each itinerary includes a set of segments, and customer choose itinerary, in here customer can not change the segment in each itinerary.
so i doubt that how can customer change segment in the uc of Change Itinerary?