The Account time zone is used for displaying monthly usage, as well as message scheduling and reporting send-time references. It also comes into play when you use the socially aware sending option to restrict your message sending to a window of sociable hours.
Note: Modifying the account timezone is a feature restricted to the admin(s) of the account. If you need the timezone updated and you are not the admin, please reach out to the admin of your account who can do this in account settings > general > account time zone.
How to Change the Account Time Zone
1. In the menu, click on the icon, then select Account:
2. Select the General tab.
3. Find where it says Account time zone, and click on the Edit icon.
4. Use the dropdown menu to locate the required time zone.
5. Now Save and you're done: