OK so if you don’t sit for the exam (for which you were formerly registered) you are no longer a candidate. This is news to me, I thought you are a candidate until results come out regardless of you sat or not for the exam.
On this line of thinking. What happens if you sit for the AM session, but not for the PM (let’s say you are taken into hospital with severe diarrohea or whatever) - you obviously will fail, but are you still a candidate or not?
May be CFAI will clarify that but i am just thinking why would you care your candidacy status while sitting on WC in pain because of diarrhea. Lol
The thought came from a practice question. 
if you don’t sit for any part of the exam, you are no longer a candidate because that means you failed.
You’re no longer a candidate because you didn’t sit for both parts of the exam, not because you failed.
Basically, on June 15th you change your linkedin profile from “CFA Level III Candidate” to “Passed CFA Level II”.
Kind of like going from “in a relationship” to “single” on Facebook 
Um . . . no.
If you take both parts of the Level III exam in June, then you are still considered a candidate until the exam results are released.
Interestingly, I could not find a definition of “candidate” in the CFA curriculum, nor did a search of CFA Institute’s website yield anything useful. I’m going to e-mail them, because I know that I have read such a definition.