nice thanks, that looked promising but I've checked a number of older articles and they have no amp version (despite the HTML for the site referencing an amp ve

nice thanks, that looked promising but I've checked a number of older articles and they have no amp version (despite the HTML for the site referencing an amp version, the url is 404!) I'll see if I can figure out if all newer pages will have permanent amp versions, or whether all amp versions drop away over time.