Periodic imports gets stuck halfway

[Shaderpixel]

On fmo.unl.edu website, BMR .csv file imports will freeze at certain percentage intervals as do file deletions. For import file deletions, the feed importer needs to be unlocked couple of times to fully purge the importer.

Found two links on the issue:
https://www.drupal.org/node/1693966
https://www.drupal.org/node/2275893

TL:DR :
Thread 1693966 says use a unique identifier in file
Thread 2275893 says On investigation it turns out that at first a job is scheduled, importing the first part. When that is done no new job is scheduled, thus resulting in an unfinished 'locked' job. Has patch in thread.