We just checked in today and room was not ready until after 4pm. Seems to be a reoccurring theme. Check in time is 4pm for the villas and they don't appear to be ready early. If you plan on arriving at Aulani before 4pm I would suggest bringing your bathing suit and make use of the pools and such. They give you your room key so you can get the pool wrist bands but you won't get the room number until the room is ready.
Good luck everyone, definitely busy this week!