Hi,
The time displayed in the email should be offset using your joomla configuration's timezone option.
You can always edit the emails via the menu System->Emails (in the Business edition) and change the time display function from:
hikashop::getDate(time(),'%d %B %Y')
to:
hikashop::getDate((time()+XX),'%d %B %Y')
where XX is the number of seconds of the offset you want.