BA are offering their Exec Club members a discount of 25% off Club Europe flights from
Fly Club Europe (business class) from London Gatwick to Tirana or Pristina. From London Heathrow the offer is valid on flights to Warsaw, Prague, Sofia, Budapest, Bucharest, Kiev and St Petersburg.
|Booking period:||10 February – 13 February 2012|
|Travel period:||10 February – 25 May 2012|
|Cabins:||Club Europe (business)|
I tried this and it works fine. You can either use the link from this page https://www.britishairways.com/travel/eastern-europe/execclub/_gf/en_gb?source=home&openxzoneid=303&openxcampaign=cfseasterneurope&openxbanner=10795&openxtype=click
or you add the voucher code above when booking: