As a SaaS solution operator, you can apply add-on updates to existing systems via theDeploy Product app in the Landscape Portal.
You can select the target add-on product and version for the update. Afterwards, you can select the systems where the update should be applied and schedule the update.
If you are using gCTS instead of add-ons for delivering software components into production systems, you need to pull the changes of all relevant software components into all productive systems using the Manage Software Components app. An update deployment via the Landscape Portal is not required.