After SCM authentification data turned invalid, further builds were marked as ABORTED in the Build History. There was no mail sent notifying of the problem!
Projects Mail configuration is shown in the attachment.

The following is shown on the console:
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Gestartet durch Benutzer anonymous
Building in workspace #################
Reverting #################. to depth infinity with ignoreExternals: false
Updating https://svn.################# at revision '#################'
ERROR: Subversion update has been canceled
Build wurde abgebrochen
Notifying upstream projects of job completion
Finished: ABORTED
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Suggested action: mark failed SCM checkout as FAILED, which would probably trigger the notification mail.
Alternative suggested action: add option to receive notification Mail with failed SCM checkout.