It killed my Jenkins instance. I had to revert (by removing the .jpi from the plugins directory and renaming the .bak to .jpi).
--
You received this message because you are subscribed to the Google Groups "Jenkins Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to jenkinsci-users+unsubscribe@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/jenkinsci-users/e2e72be1-0201-48e9-a9af-c7fc1423a122%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
But later in the day I must have upgraded again and with no ill effects. So apologies for the alarm.