Thanks for input.
I have made a pull request to fix this.
https://github.com/jenkinsci/junit-plugin/pull/123
How can I get it reviewed?
Very likely a duplicate of something much older.
There are other manifestations of the same issue in the code, e.g. JENKINS-31926, JENKINS-26153, JENKINS-25340. But this ticket is unique in that it describes specifically deleted builds - which is exactly the issue which I had.
Any news concerning this issue?