Well... I ain't no adcom so not qualified to answer that
Last year's roll call included name and the invitation date. The invitations seemed to be lumped. For instance, for R2 last year, a large number of people got theirs on 12/22 - well, I got mine on 12/22 as well. Just like other schools, I think they do it in batches, and trickle out for the special ones.
The due date for R2 was 11/4, I think and I got mine on 12/22 - relatively fast so I had to wait about a month for the D-day. Given that R3's deadline was January, R3-ers still have many days to go. Thus, keep your mind busy with things elsewhere. I read Ross and Fuqua's threads - very fun to read as the level of paranoia is out of this world.