If you or your student uses a braille display with an iOS device, do NOT update to iOS 14.4!
Currently, there is a bug with iOS 14.4 that is causing users to have trouble pairing braille displays. In addition, other users have significant lagging and/or only part of the letters/words being entered are showing up.
If you have already upgraded to iOS 14.4 and want to downgrade to iOS 14.3, here is a post that provides information on downgrading. My understanding is that if the directions listed here do not work, you can contact Apple directly and request information on how to downgrade your device.
Apple is aware of the issue.
Note: These issues appear to impact ALL braille devices. The braille devices can still be connected to laptops/computers and work fine. The issue is only for devices running iOS 14.4 software and braille devices.