ATIH 2011: Triggers of Post Commands and built-in Shutdown?

Questions
In ATIH 2011, what is the cause-and-effect relation between ...

1. completion of ...
a) a scheduled backup,
b) completion of an automatic (ATIH triggered) subsequent backup validation (check box "Validate backup when it is created.")

and

2. execution of ...
a) a (customer specified) Post command for backup and
b) an automatic (ATIH triggered) Computer Shutdown (check box "Shut down the computer after the backup is complete").

Version
Windows 7 Pro SP 1; Acronis True Image Home (ATIH) 2011, update 1 (Build 6696)

Background
In case of long lasting backup procedures, the computer shall issue progress notifications to the user (e.g. by means of Post command using "msg") and shall finally shutdown automatically. However, completion of the backup validation shall be guaranteed.
According to forum threads on previous versions of ATIH, Post commands and shutdown were triggered already after completion of the backup. The triggers did not wait for completion of the validation. Hence, a long lasting validation could be aborted by a shutdown. However, the messages issued by my Post commands for ATIH 2011 look as if the Post command is now triggered not before validation is completed(?).