When you contacted AIT did you do so over the phone or by emailing them?
When I call I always get an automated line that gives generic information when I hit the prompts for visa services.
Today I hit the prompt for "other sections" which links you to a live representative. The person I talked to was with the Administrative Department and said AIT could not help cancel or reschedule our interview date and was quick to give me the USCIS and the NVC websites. He seemed very irritated by my question actually. I also asked him if NVC or USCIS didn't respond to my rescheduling email in time and we are considered a no show at our AIT appointment what would happen to our case. Again, he said to check the NVC and
I talked to someone from UStraveldocs (department of state visa appointment service) support line and they told me AIT was the one in charge of rescheduling.
Anyways it says on the AIT website to contact VisaIV-AIT@state.gov to reschedule so I will do that. And probably NVC to to cover myself in case the guy at AIT was right or they don't reply in time.
I think I reached the wrong person at AIT.
That was long winded, if you made it this far, sorry about that!