I agree with you. I shouldn't have asked my CO to speed up the process (the process is usually very fast anyway, it is a shame that I did know that before attending the citizenship test). Now, as I recall, that was what was suggested by the Immi when I called them. It is my bad to misinterpret that.
I am able to travel to overseas using my current passport. However, I am planning not to do so before my Australian citizenship is finalised.