macOS - Catalina Upgrade Process
This article explains the Catalina Upgrade Process available in Self-Service
macOS 10.15 “Catalina” Upgrade Process
Step 1. Open the Self Service application from the Applications folder, dock, Spotlight or via Launchpad.
Step 2. From the Self-Service application search for “Catalina” and select the “Upgrade to Catalina” policy.
Step 3. If the UWM Catalina installation files are not present, there will be a prompt to download them. Some computers may already have the installation files cached. Skip to Step 4 if you are not prompted to download Catalina.
There will be a notification that the download will happen in the background. Click “OK”. When the download finishes there will be an option to continue the upgrade or postpone it. If postponed, the policy will need to be re-run from Self Service, however the Catalina installation files will not need to be downloaded a second time.
Step 4. There will be a prompt when the computer is ready to start the upgrade; click “OK” to continue the upgrade, or “Cancel” to stop. If canceled, the policy will need to be re-run from Self Service. After clicking “OK” the computer will begin preparing the upgrade, which can take up to ten minutes. The computer will then reboot and start the upgrade. During the upgrade process the computer will reboot several times. The typical upgrade takes between 30 minutes and one hour, older computers may take longer.
Step 5. The final step in the upgrade process requires the user to login as they normally would. After logging in, the upgrade will finish which may also take several minutes.