Depends on the strength of your application.
Overall: the number of interviews you'll get submitting now is likely to be less than the number of interviews you would have gotten if you had sent them out in, say, July
Effect: depends on the strength of your application. An exceptional application may still generate several IIs at this point. A weak application may struggle to generate one.
Chances for acceptance: diminished proportional to the effect size
Number of IIs you will get = A - BX where A is the number you would have gotten with July 1st submissions, B is a constant, and X is the effect size.
I don't understand your third statement. You submitted some secondaries in August, but what do you mean sitting on - you haven't heard anything from them? Or you had them finished in August but just sent them out?