On Windows, did an automatic upgrade from 1.554.2 to 1.565.3, and in the jenkins.err.log I see this:
INFO: Scheduled a replacement of jenkins.exe
Although when Jenkins comes up, the message at the bottom indicates that 1.565.3 is running.
Instead of checking the checkbox 'Restart Jenkins when installation is complete and no jobs are running', we always restart Jenkins via the Services control panel, after the downloads are complete.
I ended up updating the file manually, then restarting Jenkins.
After doing so, the 'INFO: Scheduled a replacement of jenkins.exe' message went away.
It is kind of disturbing to see that jenkins.exe was never actually updated since 05/02/2014 until today, which is when I first noticed that message in the Jenkins log.
05/02/2014 09:15 AM 50,624 jenkins.exe.old
10/15/2014 06:18 PM 55,776 jenkins.exe.new
10/15/2014 06:18 PM 55,776 jenkins.exe