1951 radio (?) adaptation with Edith Evans and John Gieguld

Does anyone know anything about the 1951 adaptation of THE IMPORTANCE OF BEING EARNEST starring Edith Evans and John Gieguld? Was it a British radio broadcast or possibly a recording made to be released on record? I believe they did record this for vinyl release in the 1950's but am unsure if this it the same production. This has shown up on the internet under the guise of the 1968 SATURDAY NIGHT THEATRE BBC radio adaptation with Dame Edith which was presumed lost but the recording clearly is introduced as being from 1951 and as part of A CENTURY OF MODERN THEATRE (another BBC program?), whether the introduction by some unknown broadcaster was part of the 1951 broadcast or added later I don't know, nor do I know if this 1951 production was indeed rebroadcast in 1968 and there was no "new" performance of the play at that time as has been suggested. Any fans of British radio (or Wilde, Evans, etc.) out there who can straighten this out?