Don't Stop Singing will be released on November 7 by Mighty Village Records through Island Records - Denny's original label before her death in 1978 - a year after Universal Music Catalogue marketing consultant Sue Armstrong passed the words to Gilmore.
They were discovered among Denny's possessions by the curator of her estate, Elizabeth Hurtt-Lucas (Fairport Convention member Trevor Lucas's widow), who approved of Gilmore - a lifelong Denny fan whose career began interning at the band's recording studios - working on scoring and recording them over the past year for release.
Mighty Village managing director Ian Brown, the Island A&R consultant who most recently enjoyed success with the Fisherman's Friends record, said: "It's 10 out of 10 for Island. They are a proper record company for the fact that they gave us the room to do something with these lyrics. That is something rare. Thea was blown away by them - it's a fucking brilliant record.
"The point of this record is that it's amazing to have six exercise books full of hair appointments and shopping lists and these lyrics, and amazing to turn these lyrics into music."
With Gilmore, who has released 10 albums in as many years, held in high regard by many music critics, extensive coverage is expected with features already confirmed to run in The Word magazine and The Independent. Radio is expected to be serviced by at least two singles, including the title track, also released on November 7.
Brown, who has handled several of Gilmore's releases in the past, adds: "It's initially about getting the fans of Sandy and Thea and making them aware of the record; there's a lot of love for them in the press and media. It starts off as not a big campaign, but the idea is that we galvanise fans before Christmas and step up the campaign in the new year with another single.
"We want people to come to the record and not force it down their throats."