It's not just security updates, there's also whether all the device management tools and techniques, training and institutional knowledge, and customer acceptance will carry over to the new OS. Whether the devices that are within AUE and receive the update are going to run the new operating system well, or they're going to languish with poor performance or broken drivers that will never get another look from the manufacturer because they're 2 generations behind in a vast sea of models and individual configurations.

I also can't find anything online to do with what they're going to do to Chrome OS Flex, so thank goodness I didn't set it up for my mum who was sick to death of Windows 11.