ASA rule question

[SouthPaw]

I was born & raised is Southern California & have been playing by the Southern California Municipal Athletic Federation rules for a few years. I now live in Colorado & am about to play in my first league with ASA rules. My biggest question is base running. In every league I have ever played in, you could lead off of a base the minute the ball is released by the pitcher, but I have been told you can't in the league I am going to play in. Is this a true rule in ASA? Thanks!!