Last time it was first come, first served once you got out of the randomized waiting room which meant the lucky few who got through first snagged up all the best reservations. This time it sounds like (fingers crossed) they are using an SDCC-style lottery where you submit all your top picks and there is a lottery from amongst all the submissions, which seems like a much more fair way to distribute the popular reservations.
They said "no overnight queuing" for the last expo too, but that didn't stop unofficial queues from forming and
D23 having to accommodate those people anyway. So unless they say no overnights and actually enforce it on Friday, there will probably still be people attempting it for Saturday.