I'm seeing the same thing... about 30% of the clients are showing the alert, and I haven't found a common thread. They are spread across 9.0.x versions, network locations, and install dates.
We have decided to go ahead and update the clients to version 10, but we definitely feel like ESET has abused us as a customer. It's not a good time for us to dedicate the resources with holiday out-of-office staff, year-end close outs, and a SOC2 audit on-going.