There is no realistic estimate at this point because we don't know how strong the prosecutor's case is. The prosecutors might even mishandle evidence and botch

There is no realistic estimate at this point because we don't know how strong the prosecutor's case is. The prosecutors might even mishandle evidence and botch the case. Insider testimony might not hold up to cross examination. SBF might succeed in arguing that he acted in good faith throughout. There's no predicting how this will play out. High profile trials (Musk, Trump, OJ Simpson, Madoff) are high variance in outcome.