I don't believe this is open to UK residents

An Eligible Participant is a British Airways (“BA”) Executive Club member, resident in one of the Participating Countries listed in Clause 2,

Participating Countries for this promotion are: Albania, Algeria, Andorra, Austria, Belarus, Belgium, Bosnia Herzegovina, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Gibraltar, Greece, Hungary, Kosovo, Iceland, Israel, Italy, Latvia, Libya, Liechtenstein, Lithuania, Luxembourg, Macedonia, Malta, Moldova, Monaco, Montenegro, Morocco, Netherlands, Norway, Poland, Portugal, Romania, Russia, San Marino, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Tunisia, Turkey, Ukraine, Vatican City.