The status screen is not displayed even if shutdown backup is performed on Windows 10 1903.
Therefore cannot cancel it.
Msgbox can not be displayed even if the script that displays Msgbox is executed by the shutdown script of group policy.
Therefore, there may be some specification changes or bugs in Windows 10 1903.
AIP2018 Update (Ver.220.127.116.1191) has been modified to display the status screen with static images.
-ActiveImage Protector 2016/2018