In early February I was invited to an interview for a PhD programme. I realise that there were only two candidates on the shortlist, and only one was going to be selected by the department. A couple of weeks later I was informed that my application was unsuccessful, so I presumed that the other candidate was not only selected, but she had immediately committed to the university well before the April 15 deadline, which is why I was informed so quickly. Then, recently, I found out that the he has actually committed herself to a different university instead. Presumably that means that there is now an open slot in the previous university, but if that was indeed the case, why didn't they contact the 'runner-up'? (i.e. me)
P.S. When I e-mailed my potential supervisor about what went wrong with my application (in February), he mentioned that the other candidate was not necessarily 'better', but he was a better fit for the department. He encouraged me to apply again next year, and that I will still stand a very good chance of acceptance if I do.