The display-maker TCL held a 2020 Display Technology Conference earlier in October 2020. This Chinese event reportedly showcased this OEM's rollable phone prototype. Now, a video purporting to contain thie footage has been posted to YouTube. It appears to show the groundbreaking device with a fully-functional extendible screen.
https://www.notebookcheck.net/TCL-s-rollable-phone-demo-allegedly-leaks-onto-YouTube.500562.0.html