I think that the "Grey Funnel Line" verse which "went missing" was probably the 3rd one in the DT version as it's often left out of songbooks and recordings - what a pity as It's probably the most significant verse in the song.

Still, Cyril's had several whole songs which have been lost and found. When he used to host his weekly west country radio programme, he tried to write a new song for each show - often on topical subjects - some of these got mislaid. I believe that "In the sidings now" (About the Beeching railway cuts) was given back to Cyril by someone who'd recorded it at the time.