I wouldn't even care about that, at least not after I have taken the oath of citizenship. To your question, yes it will change from decision made to 'complete'
Didnt know that was the reason u were asking. You dont have to wait for status change as that may take a while. After your oath you should wait 24-48 hours to allow the update to go into the system, then you can apply for passport.
Yes. It does.
I took the oath of citizenship yesterday April 24, 2018.
This morning Wednesday April 25, I checked my eCas and it was updated like this:
Application: Complete
You became a Canadian citizen on April 24, 2018.