I didn't apply early enough in the OTCAS cycle, and so I think about half the schools I applied to didn't even seriously consider my application because they were almost full by the time OTCAS verified. I actually applied to about 20 and got interview invitations for about 6-8. Unfortunately, a number of those invitations were for conflicting dates, and I also got some interview invites after I'd already had to put down a deposit at the school I'm going to.
I got accepted to two schools that didn't interview me, after the point when I'd had to commit to the other school. One was an applicant school and one was a December start date. Both schools required public speaking, and I'd already dropped my public speaking class in order to take Physics, so that left me out. Also since public speaking was a 9 am class at a campus 20 miles away, I was spending over an hour stuck in traffic to get there each day, which was messing up my sleep schedule/physical health/stress level.
Even though a school may say that its deadline isn't until say Feb 1st, I wouldn't wait until then to submit my app in OTCAS. Even if you've applied to 4 other schools with early deadlines, they may take a while to send out acceptances. Many schools with late deadlines actually have rolling admissions and take closer looks at the students who apply early.