This is a long process. I don't allow any whining about not having an interview invite until the Friday after Thanksgiving (Nov 29 this year). That's three months from now.
Faculty reviewers are reading these applications as quickly as they can and sending recommendations to the admissions office. Someone there decides if you should be interviewed and puts you in the queue to get an invitation. Some readers are slower than others and if there are 35 to review in the next 2 weeks, some people might do 2-3 per day for 14 days and some might leave then all to the last 2 days. Either way, you might get reviewed 2 weeks later than someone else whose application arrived the same day. Or you might have been held back by luck of the draw, to be reviewed later because dumping 250 applications on a reviewer at one time and saying, please do at least 15-20 per week is not a good way to handle reviewers.
Now, you might have been reviewed and recommended for review but there are so many others that we'd be asking you now if you are available for dates in the first 2 weeks of November. A lot can happen between now and then and schedulers find that they get lots of calls and messages asking to reschedule. So, to cut down on those situations, they'll hold off until mid-October to propose dates in early November.
I hope this helps calm some of your concerns.
It is a long ride to Mars. (see sig line)
