Found today by Graham Gordon. The Cliff Swallow spent all day around the pool at Porth Hellick until at least 7.30pm this evening and is the first record for Britain and Ireland for 15 years! There are nine accepted records of Cliff Swallow in Britain and one in Ireland.
Discussion on Birdforum here. Pictures here here, here & here
Fascinating account of the first Cliff Swallow for Britain in 1983 here: