Interview was moved to a different district, although I didn't move out of district
Here is my short story. Me and my wife applied in March, 2016. We were scheduled for interview in SF district for August, 4. Few weeks before the interview we submitted address change request and later got our confirmation letters. The new physical address is the same city and the mailing address is the different district. Everything remain same for my wife but something wrong happened to my case. It was cancelled and in few days scheduled again for August 30 but in the _different district_ - the Santa Clara district where my mailing address is in.
The activity went smooth. Mr Khanna provided assistance in obtaining the visa for myself and the family.