Y'all might benefit from making a running thread similar to previous years' formats.
Program (date offered): interview date options
Repeat.
If you do a search, you'll find this thread from previous years.
As for invites, not all programs send out all I their invites on day 1. I got a few a day or so after the initial offer date posted on sdn. This is less common for early programs, though, as almost no one is going to turn a program down, whether for conflicting dates or non-interest. Good luck. Hope to see some of you at our interviews.