I've only seen one report for Corfu and that was with a 2.4m Channel Master offset dish, they still couldn't get BBC and ITV. Up in Kastoria on the Mainland North and slightly East of you, someone is receiving patchy reception of some of the Astra 2D channels BBC etc, but not 24hr. http://www.astra2d.com/greece.htm .
You will probably need a 2.8m - 3m dish, but that isn't guaranteed to produce the goods.