What is a push upgrade?
Salesforce supports push upgrades as a means for automatically upgrading installed packages. Generally, push upgrades can make sure that all customer orgs are on the same or latest version of an app. This minimizes the potential risks of running outdated software versions.
JustOn makes use of push upgrades, too. If your org has recently been upgraded to a current JustOn release, you can register your org, indicating the org ID, for push upgrades. To do so, submit a JustOn Upgrade request in the JustOn Support Portal.
Subsequently, your org will be upgraded automatically and on a regular basis to the latest stable release of JustOn Billing & Invoice Management. Without you needing to do anything, this guarantees that your org always runs the current JustOn version, which, in turn, ensures a completely supportable system and allows you to use all published new features.
One week before the upgrade, we will send an email announcement giving important information about the next push upgrade. This email may indicate actions that you need to perform before or after the upgrade, and that may be necessary to ensure an error-free installation or to adjust existing features to allow using them with the new functionality.
Related information:
View Push Upgrade Details in the Salesforce Help
Pushing an Upgrade in the Salesforce Developer Documentation