Trigger in Jenkinsfile not working properly in single branch pipeline job

[tlvu]

The line below should have added the midnight cron trigger to all pipeline jobs as long as it's on the master branch

PAVICS-e2e-workflow-tests/Jenkinsfile

Line 3 in 21e85d4

cron_only_on_master = env.BRANCH_NAME == "master" || env.GIT_BRANCH == 'origin/master' ? "@midnight" : ""

It's working fine for the multibranch pipepline job

https://github.com/Ouranosinc/jenkins-config/blob/356154251ad9e535e0799a136f812eb9a57c505e/jcasc/jobs.yaml#L3-L9

but not the single branch pipeline job

https://github.com/Ouranosinc/jenkins-config/blob/356154251ad9e535e0799a136f812eb9a57c505e/jcasc_ouranos/staging_jobs.yaml#L5

After the 2nd scheduled run on the single branch pipeline job, the cron trigger disappear ! So it does work for 2 times, which makes matter even more interesting/puzzling.

[tlvu]

Asked on https://gitter.im/jenkinsci/jenkins, this bug is way too weird.