I heard a song on radio 2 today (26/06) they didnt say the name of the song or who it was by, it's not a new song, it was played in the 'oldies' part of show with Steve Wright. Part of the lyrics were something like...'we'll live together, until the 12th of never' it was sung quite high sounding similar to the communards. Thanx for any help!
I don't know if this is the version you heard since I'm not consciously aware of ever having listened to him, but there is a song called 'The Twelfh of Never' by Johnny Mathis. Ironic you should mention the Communards though - the production company owned by Erasure appears to be called 'Twelfth of Never Productions'!
If you ring the BBC and ask them, they will have a playlist of songs for that show on that day, and should be able to advise you - it's a common query for them, so they are usually helpful with listeners who call in.