What are the differences for UDI/marking for stand-alone software as opposed to physical devices?

In addition to the UDI-DI identity i.e., GTIN (Global Trade Item Number), there is also UDI-PI for version of software with AI (8012) See ref.gs1.org/standards/genspecs/ page 205. See also EU UDI helpdesk Software medical devices (europa.eu)