If the case is actually dismissed and not refiled, the defendant will be released forthwith (usually the same day). This assumes the defendant has nothing else holding him in custody (parole or probation hold, ICE hold, new/old charges). Good luck.
Immediate release usually mean several hours. In Sacramento, it usually takes 10 to 12 hours for an inmate to be released from the county jail or as I say "if it's dismissed by 10:00 a.m., you'll be out by midnight". Of course every county is different.
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