I was informed via Ottawa that the change was simply due to the trending of evolving job descriptions in the general sense of the term. Gender, civilian/military, etc was not a factor influencing the change, but rather what the perception was of the title itself. Administrator apparently implies specific training.
A good sum up:
...you might think clerical and administrative work in an office is one and the same, but they are not. Clerical personnel are entry-level workers, generally, whereas administrative work is typically done by trained secretaries or administrative assistants.
So I’d understand it that trade training sees HRAs/FSAs (Administrators) are specifically trained in their field. Not just any individual who completes random clerical tasks around the office as asked; who may, or may not, receive distinctive training in the future. (Although that ends up happening too.)