Via @rickypo on Twitter : Model(s) of the future? Overlay journals as an overlooked and emerging trend in scholarly communication
https://ojs.lib.uwo.ca/index.php/cjils/article/view/14730
For the novice, a 2019 explanation of overlay journals : https://blog.scholasticahq.com/post/journals-using-overlay-publishing-models-equitable-oa/