According to a report from Bleeping Computer, it seems that the latest update has caused a bug with Windows’ “Defragment and Optimize Drives” tool. As a result of this bug, apparently Windows 10 will no longer record the last time your SSD was defragmented, and because of this, everytime your computer gets rebooted, Windows will attempt to defragment your SSD.
One of upsides of SSDs over HDD is its longevity due to the lack of moving parts. It is also not supposed to be defragged that often, and depending on how often you reboot your PC, it could end up being defragged several times a day which could hurt its health and ultimately how long it will last you.
Microsoft is said to be working on a fix for the bug and has rolled out a potential fix to Insiders, so hopefully it will find its way to other users soon. In the meantime, it might be a good idea to disable automatic defragging until the bug is fixed.