Usually this is caused by some unsatisfied (versioned) Depends/Conflicts/Replaces.
These packages will be automatically rescheduled for testing seven days after they failed.
The commandline to find these logs is:
COMMAND='grep -E "E: Broken packages|E: Unable to correct problems, you have held broken packages.|E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages."'
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