In NetSuite, when you change the item name on a sales order from closed periods, the system will display the current item name on the transaction. This is because NetSuite dynamically pulls item information, including the name, to display on transactions and reports at the time of viewing. This ensures that the most current and accurate item information is always presented, regardless of when the transaction was entered or modified.
While this behavior maintains consistency in how item data is viewed across the system, it's important for users to be aware that changes to item names will retroactively affect how past transactions display the item, potentially leading to confusion if historical data is reviewed without awareness of this dynamic behavior.References: NetSuite Help Center and official documentation on items and transaction management.