Friday can send out your invitation, reminder and results emails to your users in their local timezone.
Your default account timezone is set in your Account settings. This should be the timezone for your main office, or the timezone for the majority of your users.
This is the timezone used for: - All users if no other Location timezones are set, or - Particular users if a Location is not set those users
To add additional timezones to your account, add Locations, via People in the menu and select the relevant timezone for that location.
Then allocate users to the relevant Location either by manually editing the user, or via a user list import, both of which can be done in the People area of Friday.