I wrote a script, modified + tested it and that worked fine 6 months ago. I expected to use it then but didn't but all good so i kept a special branch for my script which generates data from old db, formats it to new db structure and dumps it into a collection. In fact, i ran one of the scripts last month (360 records) and it worked fine. Today, when i need to migrate 14,000 records, script refuses to run. I am ready to fight the universe because wtf.