How to Delete Operations With Inspection Characteristics 
If an inspection characteristic has been allocated to an operation (system status ICHA), you can delete the operation providing
To delete an operation with status ICHA...
This will ensure that the inspection characteristics of the remaining operations remain in the process order.

Remember, if you delete an operation which has already been released, the system activates the system status DLFL in the operation, but leaves the operation in the operation overview.