hello Michael,
I don’t have any personal experience of this issue but I do recall when working in Plymouth that the Local Authority were purportedly having issues with the North Prospect estate which was an inter-war development. If my ailing memory serves I seem to recall that the Council were looking at insulation removal costs. The estate has been substantially redeveloped since but there may well be someone in the Estates or Building Surveying departments who might have some info for you.
Good luck with your research and I look forward to seeing your published findings; many surveyors in this part of the world incur the wrath of insulation installers for telling our clients not to risk it!
Kind regards, Tim Dunne, Underwood Wright Ltd.