Just been watching the flight acitivity on http://www.flightradar24.com/ . There were 4 BA aircraft in holding patterns over the Irish sea, West coast of Ireland and 1 between liverpool and london. These BA aircraft look to be heading to Shannon airport which must have been kept open to allow these aircraft to land. BA274 from Las vegas, BA218 from Denver, BA284 from San Francisco and BA84 look like they are some of the diverted flights. But your better checking the actual airline sites for the best updates.