Are you talking about /Library/Caches/com.apple.desktop.admin.png?
That file is somewhat volatile as that dir can empty with a Safe Boot, maintenance apps, etc.
It's not something you can change that I know of.
Not sure if/why QuickAdd would nuke that - but maybe someone else has an idea.
I actually ended up figuring this out. I had an Update Inventory Policy and it was set to delete user and system caches. So at enrollment, it ran and nuked it. It was not the quick add package but my global policy. Since I have implemented Sites, these little things keep popping up. My next project is to audit all my policies and see what potential fallout there may be for people we take on in our JAMF instance. Most of the departments are still using Monolithic imaging so these things will happen. I have never put anything in caches so I never considered that the policy would cause the issue.
Thanks @scottb
/randy
Good to hear, @Randydid. Usually, it's "me" and the growing number of possibilities that lies buried the answer ;)
Scott