Certain tests, eg Initial Issue GR3 and GR1, META Approvals, will require 7 day notification instead of 1 and will either be conducted by a CASA officer, Core ATO if none are available and so on down to the regular ATOs (as far as I understand) in an effort to raise the quality of successful applicants.
Some people (rightfully so) are sick of seeing GR3 instructors who can't perform in x-winds or at AoB's greater than 45deg.