Sharing my bio experience at ASC NYC Manhattan this morning: Notice for 8/26. I used the USCIS website to reschedule, and it was very easy. The notice arrived on 8/16, the same day I went to the website; many dates were available immediately on the following days (8/19 in my case). After that, it went to pending status (Friday afternoon), and Saturday evening (surprise, around 11 pm), getting an e-mail notification, and a printable notice was available to download from my USCIS account. This morning, there were no issues at all. One guy in front was trying to walk in, and he was struggling with the security guys, but in the end, they let him in. So, just a consideration, if you want to reschedule, this was very easy.