I have an environment with a single 11.4.1 Primary server ZCM appliance, a Windows proxy server and multiple Windows WS. I would like to upgrade to 11.4.2. I would like to have 4 groups of machines get the update as follows:

A. Primary Server
B. Windows Proxy server
C. Test WS
D. All others

Here are my questions:

1. Should I choose the 'Deploy to Selected Devices' and then first do the Primary server, then the Windows Proxy server, then the test WS? If I do this, assuming everything is successful, how can I do stage D, assuming the previous stages were successful?

2. Should I use stages instead? If so, I am unclear how the Stage Timeout works. Let's say I have 3 test WS and add them as members of group 3 which would be stage 3 in ZCM. By default it will wait 3 days for those WS to update then go on to the next stage. What if I get all 3 WS to update in day 1 then in day 2 I want to do one more test so I add another WS? Does the clock reset and the 3 days runs from when I added this 4th WS? Or does the 4th WS get updated at the end of day 3?

How do others deploy these system updates?