on our side, we take DB rules schema dump from tested & controlled environment and we load it in Prod.
with circumstanced rules, we can make sure not to break any specific environment setup.
Then we apply SQL & load all required data instances before final restart.
We're allowed of Prod downtime which allows also such approach.
This might only help reducing the deployment part.
For business validation, I guess you'll need to play with specific access group for testing new version while your system still points to previous versions.
When validated, you'll need to align all required AG to new version.