This is a feature that allows for dynamic background wallpaper and lock screens that rotate background images daily.
You may notice your desktop wallpaper will change to Windows Spotlight, along with a different background image than you had previously. If you wish to change it back to a static background or image, you can do so by using the personalisation options in settings.
Windows Spotlight has been the default for some time in Windows 11 but can be changed in the same manner.
If you have any queries regarding this, please contact the IT Service Desk at IT.Services@lboro.ac.uk.