I upgraded the PostBuildScript from 0.17 to 1.1.0, and it completely messed things up for me. I ended up reverting, and rolling back the config changes.

There are two problems:
(1) The previous behavior was that the script ran on the agent. When you upgrade to 1.1.0, all your jobs get set to auto-run run on BOTH (master and agent). It should keep the previous behavior for existing jobs.
(2) When you upgrade to 1.1.0, all your jobs get an additional configuration option added, which is when to run the step (SUCCESS, FAILED et)c. All existing jobs get upgraded with no condition selected. The result is that updating to 1.1.0 means none of my postbuildsteps run. When upgrading an existing job, it should preserve the existing behavior and run on all exit conditions.

I don't know why you added the "run on SUCCESS/FAILURE" anyhow - it was already possible to do this using the Conditional BuildStep Plugin, which integrated well with PostBuildScript. Why add code to duplicate and existing function?

Also, the Jenkins update center correctly tells me:

Warning: the new version of this plugin claims to use a different settings format than the installed version ... Consult the plugin release notes for details

However, there are no release notes with any detail.

Sorry, I don't want to sound grumpy, and I appreciate that the plugin is getting some attention, but I think in this case insufficient attention was paid to the effect on existing users of the plugin.

I think it would be best if 1.1.0 was withdrawn from distribution until the above can be addressed.

Thanks