Overall, the system works on a permissive basis and you can only change certain allowed items depending on an Order/Line Item's current status. This is to help ensure data integrity as a print progresses through the manufacturing process. To see the rules around changing these statuses, please see this page.
As a reminder, the high-level flow of statuses can be seen below. Full status definitions can be found here.:
New > Pending > Confirmed > Complete/Cancelled
Line Item or Order status of New or Pending:
you can change any data within the line item/order
When the Line Item status is Confirmed or higher:
You can change:
Model Units
Layer Thickness
Notes
Material
Design Hours (but the price won't update based on them)
You cannot change (this is not an exhaustive list):
Model/Design File
Service Provider
Please note: The Production Workflow is able to be amended once the printing run has been completed via the production change mechanism. This process is outlined in this article.
When the Order status is Confirmed or higher:
You can change:
Model Units
Customer Information/Shipping Information
Order Owner
Notes
Custom Fields
You cannot change:
Order Offer/Quote Information