Your welcome! I do love google.

From that last link, yet another State Farm person indicating they don't cancel just for breed reasons....

* "If the dog is growling or aggressive, that's pretty much a tip-off that you could have a problem dog," said Dan Hattaway, a specialist on home insurance at State Farm. Mr. Hattaway said State Farm did not think blacklisting of breeds was an effective way to screen for danger. "Simply by naming a breed," he said, "people are screening out a fair percentage of good dogs. Just because someone is a Rottweiler fancier doesn't mean they have a dangerous or aggressive dog." (From a March 30, 2002 New York Times article.)
Funny they say one thing but certainly did another in your particular case. Have fun making them eat their words.