if both of you agree on the terms of your divorce you can still be divorced after 90 days.  you can go into the 3rd floor ex parte department in room w-325 after your papers are finished and complete the divorce.  the reason that trial date is set so far out is the court is backlogged and if you guys fight, you essentially have to wait your turn to have your day in court to determine all the FINAL MATTERS regarding the divorce and custody etc.. BUT that does not mean you can not file a motion on 2 weeks notice and submit sworn declarations and evidence showing why the Family Court should not appoint you primary residential parent right away. 

the 90 days is a so called cooling off period.