In CA, the actual dismissal doesn't happen until after traffic school is done with. Perhaps when you're done and the points are removed your rates will go back down. Have you attempted quotes with other insurance carriers? I know it's most convenient to just stay with the company you have already, but maybe another insurer will look at your driving record in a different way. I always tell my DUI clients to shop around for new rates. Give it a shot.
Are you sure all of your charges were dismissed? If you have 12 demerit points as a result of these then you were convicted of something. You do not get assessed points in Virginia unless you are actually convicted of an offense. You may have had all of your charges reduced, but it sounds like the 12 points are hurting your rates and those are based on actual convictions.
Your insurance company's rates are a private, contractual matter. They can raise your rates even when you get no tickets. You are free to shop around for the best rates.