Employees can confirm an itinerary in E when flying for business reasons.

IME, E inventory is made available judiciously in order to avoid spilling revenue. It would be clever to use E inventory as a switch for CFC since it could be viewed as a built-in indicator of whether a flight is sufficiently empty. However, RM systems are always more complicated than they seem so it wouldn't be a shock to learn that E inventory is but one of many inputs into the CFC-offering engine.