What are points to consider when replacing the SQL Server service account?
If you have Kerberos in the mix you may run into SPN issues. – Jeff A

Depending on your domain functional level (need to be 2012 I believe), you could use Group managed service accounts – Bob Klimes

Any manually created SPNs will need to be deleted and recreated. Any SPNs automatically created by the service on startup will be removed on shutdown, so that shouldn't be a concern. I'll second Bob Klimes' suggestion that you should go to Group Managed Service accounts, if possible. They're absolutely fantastic. Finally, you may need to configure service account permissions within each instance depending on your current configuration. Generally these accounts can be minimally provisioned, but it'll depend on your current config. – John Eisbrener

PowerShell can be used to automate – Bob Klimes



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