The permissions class: UcAddressesPermissions

This class checks for view, edit and delete access for a single address. So whenever you want to check permissions for address access, you should not call user_access(), but call the appropriate method in this class. Call canViewAddress() for view access, canEditAddress() for edit access and canDeleteAddress() for delete access. The class will then take care for calling user_access() itself.
If the permissions defined by Ubercart Addresses do not fit your needs, you are able to get further control about address access by implementing hook_uc_addresses_may_view(), hook_uc_addresses_may_edit() or hook_uc_addresses_may_delete(). See uc_addresses.api.php - included with the module - for more information.