can I change the FP date?

I filed I-485 on July 2nd and received the FP notice today. My appointment is next week, but I am going to attend a conference in another city and can not come back by the appointmenttime. I saw that I can request to reschedule the appointment date with the local ACS on the FP notice and I am going to do it. Has anybody ever done this before? Will I have any trouble in the future? I am the primay applicant. But my hu*****and will go ahead to do his FP next week. I guess this is OK. Does anybody has the same experience to share? Thanks