I had to change the verbiage in our login screen config profile, the laptop shows the updated config profile under Sys Prefs --> Profiles, but when I shutdown / power on the laptop it's not displaying the changes at the FileVault login screen (retains the original information).
Solved
changing login screen disclaimer via configprofile
+23Best answer by ImAMacGuy
I ran the following and it seemed to correct it.
diskutil apfs updatePreboot /
+16Apple expected behavior ....
It was two years ago but I had to use a profile and script...
and the script included
defaults write /Library/Preferences/com.apple.loginwindow LoginwindowText
rm /System/Library/Caches/com.apple.corestorage/EFILoginLocalizations/loginui.efires
and a forced reboot...
C
PS we also changed motd
+23these are both config profiles, no script... though there is a script that updates terminal's motd, but not the login screen's display
+16What is the domain/key for the FV widow? With new imaged machines a single profile works, but on older systems to change the message to change was a pain .. I had to open a ticket with Apple and there was a lot of trial and error and back and forth....
C
+23Not sure what the domain is, they were made from the config profile on the jss.
+23I ran the following and it seemed to correct it.
diskutil apfs updatePreboot /Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.