Although I'm in SF county maybe this will help a bit. I also postponed a jury duty - SF paperwork also says you can only do it once and have to pick a Monday within a certain time period. I postponed it to an August since my work/travel is always slow that month. Then my boss decides to have a meeting that week. I called the jury office (or whatever it is called) and explained and they let me pick another week.

Of course when I went I then was asked to do a trial involving the police - my thoughts are a little different, thinking most cops work in conjunction with the DA which is politicaly motivated - I was asked to leave rather quickly, with a big smile from the public defender.