Early renewals seems to be standard industry practice for any service that is on a subscription basis. They want your money early. Earlier this year, I bought a subscription to a national monthly magazine. In the second month, we received a bill for renewal, 10 months early. Been getting them every month now. I won't be renewing that one.
Geez, never give them access to your credit card or checking account for auto-renewal. You have little control over that. Challenging the charge (you still have to pay the charge while challenging) may not work, you gave your approval for the charge beforehand. DirecTV and Sirius are 2 of the worst for this.