It's advisable for you to apply as early as possible, before all other applications flood in and delay yours in the end. September is the main intake and you are seeing numbers close to 1000 (or more than?) who can get a place in the university (not to mention those who didn't make the cut).
There should be an official date, like maybe a month/2 weeks before the term starts, but don't go with that, go with the earliest date you can make it after you get your result. Trust me, you'll thank me.