Once a vehicle has a Vin and in C or higher status it is in the plant system with a build week it is scheduled to be built. Of course that could change because of shortages, line issues, etc. But the estimated build week is in the system for C and higher status so they can arrange for parts to be delivered within 2 weeks of the build week when your order hits D1 status.
All reps have access to the system, only certain Stellantis employees have access. That's how they can go in and push changes someone wants to make. I've done this to my order and have looked up hundreds of build weeks for people earlier this year when I had access to the system. Its about 90ish% accurate baring shortages