Today one of my colleuges had an issue with applying a hotfix in a customers environment. The environment had three AOS instances installed on the same server which had the correct version and they installed a fourth one which they missed to patch.
When we ran the axupdate install file we got this screen:
It said that there is nothing to patch… which there was… weird. So looking around the internet I found out that there is a command line parameters for axupdate called AOSINSTANCENAME… great… that should work…
Doh… turns out you cannot use comandline parameters unless you run a completely silent install…
axupdate.exe AcceptLicenseTerms=1 AosInstanceName=04-AX183ByggUserTest AosStart=0 HideUI=1 InstallAos=1 LogDir=”c:\Temp”
If you miss the HideUI=1 it will also ignore all of the other parameters 
Well… all well that ends well
Merry Xmas
/Johan