The waiting time at this time of the year will certainly be longer than in quieter months. Remember you have all the university graduates, A-level school leavers and the main holiday period; these all overload the system which is also running at lower capacity.
For what it's worth, for others next year etc, I applied before I sat my A-levels and had my OASC interview in June before school had even ended. I was given a provisional acceptance and a subsequent entry date of October, in other words about 4 months from applying to entry. There was an entry every month. With 3 entries per year you may expect up to an additional 4 months.
That was some time ago but in terms of recruitment and training the system would be running at similar timing now; in those days there was no AFCO stage.
Think carefully what you will do between AFCO and OASC as this will certainly be interview fodder. Plan for a period post OASC too, this should be a long term plan for obvious reasons.