Vespar, in an interview (that happened at the end of fan fest) Yoshi said that the ceremonies won't be hold by GMs so technically, all you'll have to do is get yourself a timeslot (not that it'll be easy tho x3) ceremonies are reset every week, so it won't take ages to get one really, that is if you can make your reservation before the hound of hyena that camped on the lodestone for the very same reason