Statutes of limitation govern the state bringing the charge. The warrant means the charge has been brought, and the SOL shouldn't be in play.
The SOL on misdemeanors is commonly one year, but it depends on state law.
"i was told by an attorney that for misdemeanor bench warrants it was one year is that true?"
I suspect you didn't tell him about the warrant's existence, or he doesn't practice criminal law.
It's POSSIBLE your state has crazy laws.