Their latest post on Pixiv and Patreon was on May 31st. The post is locked so I can't view it. But on Twitter they have a more recent post on June 11th with Karin from Blue Archive. They had posts depicting Aether, Shenhe, and Ganyu during May but I don't know if he's even working on a video with them. I know this doesn't really answer your question, but it's the best I.
tldr: Most recent update on June 11. Only character updates, no video updates.