For me (Inside worker), a bid list was posted the beginning of october & I put my name on it. About 3 weeks later the center called me & told me to meet driver so & so at a certain location.
So yeah, ask around your center if a bid list will or has been posted someone will be sure to help.
Also like an earlier poster stated, they may limit your hours as a helper to keep from giving you overtime (over 40 total hours a week). As of now I only work 2 1/2 - 3 hours a day with my driver .