Sales order item for service (project): delivery status and item editability

good morning experts,

I would like to submit some questions about Sales Order, in particular regarding item type "Service - fixed price (project)".

Once the sales order has been released, the header status becomes "In process". The item changes its delivery status to "In process". After that, item quantity and description are NO MORE changeble. I asked SAP about this behaviour and they replied that "after the order has been released, the delivery status changes to "In Process" too (This usually means that a customer demand has been created). This then locks changes to the items that are already in the document, in order to prevent inconsistencies with future documents".

Now, I have the following questions:

1. If I add a NEW line to same document, such line is changeable and delivery status is "not initiated". Why such different behaviour?

2. Even if the description is not changeble, the item Notes for Customer (Customer information) can be added. I think the item Notes for Customer should be blocked as well.

thank you in advance,

regards

Rossano