I too just finished a years worth of payments for an extended warranty, up to 120,000 mile coverage. I was told the same information about going to a still active dealer to cancel it.
45 miles away they are so, I phoned them and spoke with a woman in the contracts department. She faxed me a one page form which I emailed back. She said on the phone I should receive the full $945. back in a couple of weeks.
I received $525. or so back by check. I phoned the 800 corporate number and was told that the small print said that is all I get back.
I never used the contract and DC gets to keep the cash.
First time I have bought one of these contracts and the local dealerships near me close. Never buy an extended service contract. You are taking out a bet that the car will fail so you get your money back. But the house is betting that they will not have to pay you back.

Your refund was prorated if you have more then 36,000miles when it takes effect.