Release Management RLM - 862 DELJIT - Update Order Line

We have 862 shipping schedules coming in via EDI (via RLM interface tables) in Oracle that add order lines based on existing setup. We have a requirement from the business as they switch an item to a different cross reference (customer item = A, current internal item = X, new item no. = Y). Based on the current setup, it adds order lines with item 'X'. They are requesting that when they make the switch over from item X to Y (in customer item xref by disabling X and enabling Y), for all new 862 schedules, they want existing open