It seems like a commit with [skip ci] in its commit message is never "consumed" if the build is also deleted and continues to enforce skipping forever. With more and more commits becoming part of the "most recent build"

Steps to reproduce:

Create a pipeline jenkins file containing:

pipeline {

    agent any
    stages {
        stage('CheckSkip') {
            steps {
                scmSkip(deleteBuild: true, skipPattern:'.*\\[skip ci\\].*')
            }
        }
....

Make a commit that has [skip ci] in its commit message. Push

Make a second commit that does not have [skip ci] in its commit message. Push

Expected result:

The second commit and push kicks off a build that is not skipped

Actual result:

The second commit and push does not kick off a build (and Jenkins believes that the job contains all commits since the first skip. This continues for the 3rd, 4th etc push until deleteBuild is turned off, then it calms down and builds are allowed again.