Consider the update lifecycle
When you create a tenant-specific customization, or an extension that is scoped to a single Business Central environment (often referred to as per-tenant extensions), you must take the lifecycle of the extension into consideration.
You're responsible for your extension. You own the process of updating the extension and providing upgrade code if the schema changes between versions of the Business Central base application. When an update is available for your Business Central environment, all extensions, both Marketplace extensions and tenant customizations, must be compatible with the next version of the base application before the update can be installed on the environment. You're responsible for ensuring that your extensions are compatible with the update version.
Automated extension validation
An automated service validates all tenant customizations before an update is marked for a scheduled update of an environment. This validation compares the extension's dependencies with the updated version of the Business Central application to see if any changes caused incompatibilities with the new version.
If the validation service discovers any tenant customizations that aren't compatible with the update, an email notification is sent to the tenant administrators listed on the Notification recipients tab of the Business Central administration center.
At least one email address must be specified as a notification recipient to receive the update notifications. If you don't specify an email address, you won't be notified of updates and other changes to the tenant.
The email notification provides information on the incompatible extension, detail on which properties must be updated, and steps to bring the extension into compatibility.
Update failure notification
If a Business Central environment has an extension that isn't compatible with the update version, the update can't be applied. If an update fails due to an incompatible extension, a notification is sent to the tenant administrators listed on the Notification recipients tab of the Business Central administration center.
The notification is similar to that provided by the automated extension validation. It provides information on the incompatible extension, detail on which properties must be updated, and steps to bring the extension into compatibility.
Automatic extension removal
The publisher of an extension must maintain compatibility with the new release of Business Central. Each major update cycle follows a fixed set of periods that determine what happens when an extension blocks the update:
Preview period - A preview release is available about one month before the announced release date of a major release. Business Central automatically tests per-tenant extensions running in production for technical incompatibility with the upcoming release and notifies the notification recipients.
Update period - Starts when the new major version becomes generally available, typically the first workday of every April and October, and lasts for five months. Administrators can schedule the update on any day in this period.
Grace period - Starts when the update period ends and lasts for one month. The update can no longer be rescheduled to a later date, and users in the tenant might get more active warnings about the incompatibilities.
Enforced update period - Starts when the grace period ends. Any extension that causes the update to fail might be uninstalled automatically so that the update can succeed. Data that belongs to an automatically uninstalled extension isn't deleted, and you can recover it by installing a compatible version of the extension after the update succeeds. However, a compatible version isn't installed automatically on the environments it was uninstalled from.
For more information, see Maintain Marketplace apps and Per-Tenant extensions in Business Central online.