ok,it now makes little sense about the issue. Changing the version of CI do not change the CB Version until you do some modifications to CB.
By Default,the CB always use the latest version of CI(Which you set via CB Properties).
I looked at the client WMI to find if there is any info about what CI Version did the client receive but no info. May be you can try verbose logging if that track any additional info into logs.
try to look at CIStatestore.log ,it will tell you the CI version with Priority .I believe,the priority is nothing but the CI Version.you should see something when New CB applied with any CI changes with line An existing CI state is changed