Hi @yueminspb - we have been over this with Adobe techops with one of our instances and we have been told that there is no way to change the timezone of the server or database once the system has been configured. All dates/times in the database are stored as UTC, so this means you need to ensure that your workflows are executing in the correct timezone by setting the properties of the workflow, otherwise they will run in the Default (server) timezone. It's worth creating a workflow template to ensure this is always set.
You also need to ensure that your Operators have the correct timezone set so they see the dates for logs etc being correctly adjusted to the right timezone. If you do both of these, you wont really notice the incorrect server/db timezone.