Before latest steps updating version
This scenario describes the process for upgrading code from an earlier release to the current release.
A code upgrade is required when you deploy new environments as part of the process of upgrading your application to a new major or cumulative release.
Upgrading any additional Tier 2 or higher sandbox environments You don't have to upgrade any additional Tier 2 or higher sandbox environments.
Instead, delete and redeploy them, and then make a database refresh request to copy a database from a Tier 2 or higher environment that has already been upgraded.
If your environment is already live in production, the source database is a copy of the production database.
This step is a validation process that is done by a developer.
It helps the developer verify that the data upgrade can be completed successfully by using the specific set of customizations in this environment.
To make a copy of your production database, follow the steps in Copy a Microsoft Dynamics 365 for Finance and Operations database from Azure SQL Database to a SQL Server environment.
A developer must complete this process before other activities can begin.
Dynamics 365 for Finance and Operations version 8.0 and newer, does not allow customization via overlayering of Microsoft models.