According to the last
Wall of Shame thread, many rejections start in January. With rolling admissions schools, rejections can come a month of two before that. For regular admissions, acceptances and rejections are often sent out a set time after the interview. If you don't receive an interview, the notification tends to come earlier. Still, my Shenandoah rejection came three months after application completion.
So if you apply now, then it'll be a while before you are rejected. Do take into account any interview offers too as that bides your time before rejection.
Finally, let's talk on a positive note. After an interview, acceptance times may vary. For my Wingate acceptance, that came a few days after my interview. For my Iowa acceptance, that took four weeks!
My Creighton acceptance came two weeks after the interview. So, it varies per school. Many people who get accepted off the waitlist hear about it in May. I have a friend who got off the waitlist in the August right before the school year started!
In general, any acceptances happening a month after is considered not average. So, you won't be waiting forever.