I doubt that you are correct.  The last time this story ran, Commissioner Bozievich was very nuanced about who was being released.  I believe his phrase was   “No Measure 11 violent offenders were released due to jail capacity constraints in 2015, he said."   That leaves quite a few other Measure 11 mandatory sentencing crimes where the offenders weren't "violent" as well as serious crimes that aren't mandatory sentencing crimes.