Endpoint Protection

I am ugrading our clients from 11.5 to 11.6 using the group install package deploy method and I am trying to figure out how to find a log that shows when the machines contacted the server and started the upgrade. I have tried using the reporting but the reports are not matching my scheduled upgrade time of 9pm to 8am.  So I know i must be running the wrong reports.  Any advice is greatly appriciated.  Thank you.

click on monitors
logs
system
click on advanced at the bottom
select client server activity log; you wil get the info

http://service1.symantec.com/SUPPORT/ent-security.nsf/docid/2009081411193948

Here is a article using which you can check for computers with online status and not checked in status

Title: 'How to identify clients that have not checked into the SEPM'
Web URL: http://service1.symantec.com/support/ent-security.nsf/docid/2010020812104548?Open&seg=ent

Adding to this When you check for Computer status Log in Monitor Tab, there is a Column for Last Checked in, this will give you the time when the computers last connected to the Console.

This data can be exported.

Here is a screenshot for the same