Follow-up:
Thanks to the ReleaseReason tip, I was able to determine that the unexpectedly released job was being condor_released, and so I wrote a wrapper script to log the process tree and environment each time that condor_release was run, which led back to another housekeeping
job that was releasing held jobs if a given mountpoint was operational, apparently assuming that any held job was held because of a mountpoint problem..
Michael V Pelletier
Principal Engineer
Raytheon Technologies
Digital Technology
HPC Support Team