doesn't matter whatever changes you are bringing to it, only requirement is there should be no discrepancies and misinterpretations when the VO is assessing your file.Another question,
I have not changed my NOC even once.
But I have made some small surgical corrections in my express entry profile..i think 7-8 times since my submission.
I hope that doesn't negatively impacts my chances to score an ITA, which already looks very dim..ha ha