You get 4 months from September -January. Not sure why it's set up that way.

I am now a 1099 and am paying estimated taxes for 2014. Why is the schedule set up that you pay in April (which I did) and then just 2 months later in June? Why wouldn't it be every three months? It is throwing me off a bit because I usually put aside 1/3 of the money I earn per month, so I am basically 1/3 short this payment.