An upgrade project is more or less complex, depending on several drivers. There are IT-related and business-related complexity drivers.
To improve the long-term predictability of the Business Suite and in support of the Innovation Strategy and Roadmap, the standard maintenance was extended.
SAP extended the mainstream maintenance for SAP Business Suite core applications until December 2027 - via extended maintenance even until December 2030.
For details, check the Product Availability Matrix at https://support.sap.com/pam.
You can find the SAP Innovation and Transformation Newsletter at https://www.sap.com/cmp/nl/sap-innovation-and-transformation-newsletter/index.html.