These deadlines determine when various conference submission and review functions can be accessed.

Paper registration deadline: 15 Apr 2015 11:58pm EDT
You can register new papers until this deadline.
Paper submission deadline: 27 Apr 2015 11:59pm EDT
Papers must be submitted by this deadline to be reviewed.
R1 response deadline: 10 May 2015 12am EDT
You can submit R1 responses to the reviews until this deadline.