Earlier (on February 13, 2020), Android Police spotted a page for a new Android Developer Preview on this OEM's website. However, its download links never went live. Now, this page is back to its old Android 10 self, suggesting that the new version is still not here in any form after all.
https://www.notebookcheck.net/Google-builds-hype-for-the-Android-11-Developer-Preview-by-mistake.453921.0.html