Microsoft has been doing a lot with the Windows 10 updates this year. The latest round patches a number of security holes as usual, but with a certain caveat. Depending on the Bluetooth device, it may not work with Windows 10 anymore after the latest update.
On the Windows support page, Microsoft says that this will be the case with updates from 11 June and later. It cites CVE-2019-2102, which essentially allows Bluetooth low Energy connections to be hijacked, and used to remotely inject keystrokes. The vulnerability was also initially reported as an Android vulnerability.
It doesn’t look like there’s any way to tell if your Bluetooth devices will be affected though. The only way to tell is to actually update and see what happens. If your Bluetooth device stops working, then you’ll have to check with with the company that makes your Bluetooth device and see if there’s an update that can fix this.
While it’s unfortunate for anyone who’s affected, it’s a security hole that Microsoft needed to plug. You can delay your update for 35 days, if you are worried and need extra time to get an update for your affected devices.