RESCHEDULE APPOINTMENT

Hi My H1 B visa interview is scheduled for 29th Sept in chennai.But due to verdict on some polition the situation in chennai may be tense. I checked USTRAVELDOCS site but the cancellation or rescheduled appointment link says “booking cant be cancelled or rescheduled” IN this case how should i reschedule the appointment. The call center is off today and will be working tomorrow only.