After upgrading to 14506 this past weekend, I am getting reports from technicians that submitted changes are not going through, and it looks like it has to do with the workflows.

Many of them are suddenly showing as "Invalid workflow" and I cannot figure out why as there is no history records found. But there doesn't appear to be any problems in the workflow itself either. Can anyone advise what I can do to restore an invalid workflow so that my change process can continue?