It depends on the type of server you are using. If you are using a shared server, it is not possible to change time zone. Because time can be set only once in a single server. So, if the service is provided from a shared server, we can not change time zone according to each customer’s requirement. In such cases, we generally put GMT 0 as time zone.
However, if the service is in dedicated server, we can set the time zone according to the demands of the customers.