If email shows the wrong time
When you send or receive email, the time it was sent or received appears in the email header (the information at the top of the email). If the time shown in your email header is incorrect, you need to change the time zone setting for your iCloud account.
Change the time zone on iCloud.com
Click your account name, then choose Account Settings.
Click Time Zone, then click a time zone on the map.
You can also click the time zone name below the map, then choose a time zone from the pop-up menu.
You need to log out of iCloud, then log back in to see the changed time zone in iCloud Mail.