Extreme Networks has published a new Field Notice.
FN-2020-451 describes an issue when using UDLD on interfaces with SLXOS 20.1.2 or SLXOS 20.1.2a which cause interface flaps.
You can find full details (including software fix information) here: https://extremeportal.force.com/ExtrArticleDetail?an=000090922
If you have additional questions concerning this information, please contact your Extreme Networks representative.
The Extreme Quality and Services Teams